• Journal of Navigation and Port Research
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• v.39 no.3
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• pp.173-178
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• 2015

In these days, the world has been increasing the development of various underwater vehicles such as ROVs (Remotely operated underwater vehicles) and AUVs (Autonomous underwater vehicles). And the importance of submarine's maneuverability is especially being emphasized. Therefore, accurate values of the derivatives in equations of motion are required to control motion of the submarines. The aims of the present study are to experimentally derive Hydrodynamic derivatives derived by the vertical planar motion mechanism (VPMM) model test, and to estimate vertical dynamic stability was estimated by using the linear hydrodynamic derivatives, the hydrodynamic derivatives of the submarine, which have a high propriety, were provided by using the fourier analysis of measured forces and moments. Furthermore it is confirmed that the experimental derivatives shows well agreement with the theoretical estimations, and the dynamic stability of the submarine was estimated as a good state, which implies that the value is greater than zero.

• Journal of the Korean Society for Advanced Composite Structures
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• v.3 no.1
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• pp.8-15
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• 2012

The initial clamping forces of high strength bolts depending on different faying surface conditions drop within 1,000 hours regardless of loading, any other external force or loosening of the nut. This study is focused on an expectation model for relaxation of high strength bolt, which is confined to creep on coated faying surfaces after initial clamping. The range of this experiment is limited to estimate the relaxation of bolted joints coated by inorganic zinc primer. The candidate bolts were dacro-coated tension control bolts. The parameters of coated thickness for the faying surface were 96, 168,and $226{\mu}m$ respectively. From experiments, it exhibited that the logarithmic function for creep strain was derived due to the parameter of coating thickness. By using the creep strain, subsequently the quantitative model for estimating long term relaxation of high strength bolt can be taken with the elapsed time. The experimental results showed that the relaxation after the initial clamping of high strength bolt rose to a much higher range from 10% to 18% due to creep of the coating as the coating thickness was increased. This study showed that the clamping force reflecting relaxation after the elapse of constant time can be calculated from the initial clamping force of high strength bolt.

• Journal of the Korean association of regional geographers
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• v.10 no.1
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• pp.9-22
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• 2004

This paper aims to identify the role of local governments in building regional innovation system. The central government has recently decided to support the promotion of innovation capacities of local innovators and innovation networks among thor The central government forces local governments to establish the council for regional innovation in order to implement these goals. Meanwhile, there is no consensus about the way in which the council for regional innovations constitute and operate. I think it is the time for us to talk about this seriously. It is widely conceived that local governments in Korea have still been hierarchical. Thus, they would be difficult to make the decision effectively on regional innovation and development initiatives. In this context, I suggest that the regional innovation promoting agency needs to take authorities to secure transparency and autonomy in planning, implementing, evaluating regional innovation initiatives. The local government no! ed to play a central role in establishing the agency. However, the local government should not try to intervene and control its operations.

• Journal of the Korean Applied Science and Technology
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• v.37 no.2
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• pp.354-361
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• 2020

The purpose of this study was to investigate the effects of regular taekwondo training on neurotrophic factors and cognitive function in obese middle-aged women. Thirty-three middle-aged women with obesity were selected for this study and randomly assigned into a control group(CG, n=18) and an taekwondo group(TG, n=15). The TG performed taekwondo training 5 times weekly for 16 weeks, while the CG did not exercise training. Serum brain-derived neurotrophic factor(BDNF), vascular endothelial growth factor(VEGF), and insulin-like growth factor-1(IGF-1) levels were analyzed and Stroop Color and Word tests were performed before and after the intervention. The serum BDNF and IGF-1 levels were significantly increased in the TG after the intervention(p<.05). On the other hand, no statistically significant differences were found in the serum VEGF levels, or in the Stroop Color and Word Test scores(p>.05). These results suggest that regular taekwondo training may be affects levels of peripheral neurotrophic factors but not cognitive function in obese middle-aged women.

• Journal of Advanced Navigation Technology
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• v.21 no.6
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• pp.537-543
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• 2017

Underwater glider is the long-term operating underwater robot that was developed with a purpose of continuous oceanographic observations and explorations. Torpedo-type underwater glider is not efficient from an aspect of maneuverability, because it uses a single buoyancy engine and motion controller for obtaining propulsive forces and moments. This paper introduces a ray-type underwater glider(RUG) with dual buoyancy engine, which improves the control performance of buoyancy and motion compared with torpedo-type underwater glider. Carrying out Computational Fluid Dynamics (CFD) analysis as static pitch drift test, the performance of fluid resistance for gliding motion was identified. Based on the calculated hydrodynamic coefficients, the dynamic simulation compared and analyzed the motion performance of torpedo-type and ray-type while controlling same volume of buoyancy engine. Small-sized model of RUG was developed to perform fundamental performance tests.

• Korean Security Journal
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• no.44
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• pp.139-167
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• 2015

It is known that Psychopathy is excessively selfish, using as a tool to achieve the purpose to others, irresponsible, easy liars in common. They were recognized that it is people of harmful to society, impulsive, attacking others body, ignorant others safety, enjoying or callousing others suffers. But, another aggressive behaviors are described as pro-social aggressive acts as the cops bring under control by firearms to hostage committing a crime in social norms. The proper aggression is related with national security and safety of the people that is pro-social aggression for nation and human society. Security service with the legal grounds and the convinced commitment needs self-giving works, self-sacrificial security-activity is in the center of security service. These days, psychologists reveal the people of psychopathy are CEO, politician, broadcaster, surgeon, special forces, police officer. And they distinguish themselves and contribute to a community in various fields. Therefor, this research wanted to find out the relationship between fearlessness, coldheartedness in the PPI-R(applying to the university student for checking psychopathy, except anti-social traits) and pro-social aggression, self-sacrificial security-activity.

• Korean journal of communication and information
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• v.81
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• pp.189-224
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• 2017

The case of 'Paik Jong-moon's Taped Conversation,' has presented "an important and serious challenge to the freedom of the press and democracy" in South Korea. Nevertheless, this case has not been reported by the mainstream news media. It has also been forgotten without a proper fact-finding or investigation by regulatory agencies, like The Foundation for Broadcast Culture, The Korea Communications Commission, or The National Assembly. This study aims to examine why the above has happened through in-depth interviews of reporters and TV producers, senior journalists, former and incumbent commissioners of the broadcasting regulatory agencies, and experts of the industry, as well as literature research. Here, I present three answers. First, I found two reasons the mainstream press has ignored this incident. 1) It serves for political interests instead of reporting truth. 2) Public broadcasters' watchdog role has been neutralized. Second, regulatory agencies like The Foundation for Broadcast Culture, The Korea Communications Commission and The National Assembly are ruled by political tribalism. The ruling party's members of the National Assembly and these agencies were reluctant to investigate allegations surrounding Paik Jong-moon, such as illegal dismissals, illegal intervention in programming or production, illegal recruitment and illegal business deals. That's because they considered CEO Paik an ally. Using their majority power, they have rejected the request from opposition-affiliated commissioners or from opposition lawmakers to investigate the allegations. Third, there were no alternative forces within the public broadcasters to unveil the truth. In conclusion, the legal and institutional shake-up of corporate governance is urgently needed for public broadcasters and broadcasting regulatory agencies.

• Parasites, Hosts and Diseases
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• v.40 no.1
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• pp.45-54
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• 2002

Field trials evaluating selected commercially available mosquito traps variously baited with light, carbon dioxide, and/or octenol were conducted from 18-27 September 2000 in a malarious area near Paekyeon-ri (Tongil-Chon) and Camp Greaves in Paju County, Kyonggi Province, Republic of Korea. The host-seeking activity for common mosquito species, including the primary vector of Japanese encephalitis, Culex tritaeniorhynchus Giles. was determined using hourly aspirator collections from a human and propane lantern-baited Shannon trap doting hours when temperatures exceeded $15^{\circ}C$. The total number of mosquitoes and number of each species captured during the test was compared using a block design. Significant differences were observed for the total number of mosquitoes collected, such that, the Mosquito MagnetTM with octenol > Shannon trap > ABC light trap with light and dry ice > Miniature Black Light trap (manufactured by John W. Hock) $\geq$ New Jersey Trap > ABC light trap with light only. Significant differences in numbers collected among trapes were noted for several species including: Aedes vexans (Meigen), Anopheles lesteri Baisas and Hu. An. sinensis Weidemann, An. sineroides Yamada, An. yatsushiroensis Miyazaki. Culex pipiens pallets Coquillett L., Cx. orientalis Edwards and Cx. tritaeniorhynchus. Host-seeking activity for most common species showed a similar bimodal pattern. Results from these field trap evaluations can significantly enhance current vector and disease surveillance efforts especially for the primary vector of Japanese encephalitis, Cx. tritaeniorhunchus.

• Journal of Environmental Impact Assessment
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• v.29 no.2
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• pp.132-143
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• 2020

The purpose of this study is to identify the accomplishments and limits of the local governments' environmental impact assessment operation system and to propose a policy plan to improve it through an analysis of the current status of the operations by local governments. As the research method, based on an understanding of the basic purpose and concept of the local government's environmental impact assessment, the current status of environmental impact assessment by major local governments such as Seoul, Jeju, Busan, Daejeon, etc. is analyzed and in-depth interviews with public officials in charge are conducted. Through the extensive discussions, the current situation and the problems are identified. The accomplishments of the local governments' operation of environmental impact assessment are: it is possible, first, to select evaluation targets and items in accordance with regional characteristics; second, to continuously strengthen the management and monitoring the evaluation result after through its own follow-up control. The limits revealed are; first, internal organization problems, which are largely due to the fact that the project approvers and the environmental impact assessment consultants are the same; second, poor cooperation system between the department of environmental impact assessment and other departments; third, lack of professionalism in the working forces; and forth, a limited pool of the skilled judges; and last, it was found that there could be frequent problems of overlapping regulation during coordinating target projects and evaluation contents.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.245-254
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• 1995

The density of ATP-sensitive potassium($K_{APT}$) channels, that open as intracellular ATP concentration falls below a critical level, is very high in skeletal muscle surface membrane and those high density may imply that $K_{ATP}$ channels have very important physiological roles. To elucidate a role of $K_{ATP}$ in relation to fatigue, the modulating effects of potassium channel openers and blockers on the fatigue velocity(FV) of mouse extensor hallucis longus muscle(EHL) were investigated in vitro. Twitch contraction was induced by an electrical field stimulation (EFS: 24-48V, 20ms, 0.2-4Hz) and resulting contraction force was isometrically recorded. The twitch forces were gradually decreased to 25% of initial contraction force(ICF) in $37.52{\pm}1.55sec$($mean{\pm}s.e.m.$, n=135), indicating the fatigue phenomena. The mean velocity for development of the fatigue was measured during the period that twitch force decreased to half($FV_{0/0.5}$) and during the period from half to 25%($FV_{0.5/0.25}$) of ICF. The fatigue was induced once every one hour and the tissue response was stable for up to 4 hours. In control condition, ICF was $5.8{\pm}0.12g$ (n=144) and decreased to 50% of ICF with the mean fatigue velocity of $0.182{\pm}0.006g/sec$($FV_{0/0.5}$, n=135) and from 50% to 25% of ICF with $0.084{\pm}0.004g/sec$($FV_{0.5/0.25}$, n=135). Cromakalim($50{\mu}M$) significantly increased $FV_{0.5/0.25}$(n=4). Glibenclamide($IC_{50}>50{\mu}M$), $Ba^{2+}$($IC_{50}=10{\mu}M$), 4-aminopyridine($FV_{0/0.5}$, $IC_{50}=0.5mM$; $FV_{0.5/0.25}$, $IC_{50}=2mM$) decreased both $FV_{0/0.5}$ and $FV_{0.5/0.25}$ concentration-dependently up to 75%. $TEA^+$(30mM), E-4031($10{\mu}M$), tolbutamide(1mM) decreased $FV_{0.5/0.25}$, but apamin(300nM) and $TEA^+$(10mM) showed no significant effects. Our results suggest that activation of the $K_{ATP}$ channels may be major cause of $K^+$ outflux during development of the fatigue and the isolated EHL muscle could be an useful experimental preparation in studying the fatigue phenomena in skeletal muscle. In addition, the possibility of activation of delayed rectifier during the fatigue development remains to be studied further.