• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.1
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• pp.17-23
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• 2016

This study investigates the development of an automatic lightening buoy that can indicate an aquaculture cage at night or in rough weather. The energy for the light is generated by the linear motion of a magnet along with a coil inside the buoy as the waves cause the buoy to oscillate up and down. The principle of the magnet motion is different between the magnet and body of the buoy because the movement of the latter is dependent on the surface wave, while the former is affected by the damper. To obtain a quantitative performance of the buoy, the voltage as well as up and down motion produced by several waves were measured in the wave tank. A shorter wave period, i.e., faster motion, of the magnet produced a brighter light. It is expected that this study can aid in deciding the optimum design of a buoy capable of producing a bright light at any aquaculture site affected by sea or fresh water waves.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.2 no.3
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• pp.37-49
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• 2004

The purpose of this study was to determine the effect of spinal motor neuron excitability by cranial electrostimulation(CES). The fifteen Sparague-Dawley adult male rats were assigned to the three groups; GroupI(control), GroupII(low rate CES), GroupIII(high rate CES). Spinal motor neuron excitability was measured to use a computerized H reflex. The results of this study was as follows; M latency, M amplitude and H latency were no significant difference in all groups on repeated measured ANOVA(p>.05) but low rate CES and high rate CES groups were lower than ether group in comparative measurement of H amplitude and Hmax/Mmax ratio(p<.05). These results lead to the conclusion that spinal neuron excitability was influenced by CES. These results suggest that CES had the capability to lower spinal motor neuron excitability used synaptic blockade in spinal segment.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.24 no.1
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• pp.49-67
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• 2015

Since the implant became the important treatment modality in dentistry, the research and clinical effort to mimic natural tooth appearance have been pursued. While the rehabilitation of mastication and occlusal appearance was focused in the past, more esthetic and functional restoration was preferred recently. To fulfill this demand, the clinicians should consider the axial contour, papilla space, subgingival appearance, as well as the shape of occlusal surface. In the surgery part, there have been significant advances in the adequate formation of bone and soft tissue through the careful reflection on the surgery time and incision. When the dentist has good knowledge about this aspect and passion for the final product, he or she can acquire better results.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.377-381
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• 2006

Recently, as economy grow and population increase we need to develop our coastal area and make good use of it for various purposes. That's why large structures are being installed on the sea. Some samples are petroleum storage tanks, pier of sea bridges. These are large structures which have been installed at coastal area. When we design such vertical cylinder, we should avoid too much construction expense caused by excessive designing or by lack of sufficient design. In order to prevent excessive expenditure, it is important to correctly calculate the force of waves acting on structures and predict the wave transformation. In this study, apply to VOF method based on Navier-Stokes equation and then discussed that nonlinear wave force and wave transformation. A comparison between the numerical model and existing experimental results showed nice agreement among them.

• Journal of Ocean Engineering and Technology
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• v.24 no.2
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• pp.34-40
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• 2010

When a large ship is advancing in waves, it undergoes hydroelastic response, which affects the structural stability and the fatigue destruction of the ship. Therefore, to predict an accurate hydroelastic response, it is necessary to conduct a thorough analysis of hydroelastic response, including fluid-structure interactions. In this research, the ship is divided into many hull elements, to calculate the fluid forces and wave exciting forces on each element. Using the three-dimensional source distribution method, the calculated fluid forces and wave exciting forces are assigned to nodes of the hull elements. The neighbor nodes are connected with elastic beam elements. We analyzed hydroelastic responses, using the finite elements method.

• Archives of Craniofacial Surgery
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• v.21 no.5
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• pp.329-333
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• 2020

Mucinous cystadenoma, one of the subtypes of cystadenomas, is a rare benign salivary gland tumor. Most of the cases reported tumors presenting as asymptomatic, slow growing, single masses, primarily occurring in the parotid glands, buccal mucosa, and hard palate. This report describes a case of multiple mucinous cystadenomas that presented as subcutaneous swellings in both cheeks, which were mistaken for a benign subcutaneous tumor. A complete surgical excision was performed through an intraoral incision. There were no recurrences or complications. A diagnosis of mucinous cystadenoma was made by histopathological examination. Mucinous cystadenomas are differentiated from other salivary gland tumors based on the pathological findings. A malignant transformation is also possible. Preoperative imaging cannot identify mucinous cystadenomas because of their small size and atypical features, and needle biopsy has its limitations in such salivary gland tumors. Therefore, accurate diagnosis and treatment through surgical excision become important.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.123-125
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• 2006

This paper discusses the method of vision based sensor fusion system for biped robot walking. Most researches on biped walking robot have mostly focused on walking algorithm itself. However, developing vision systems for biped walking robot is an important and urgent issue since biped walking robots are ultimately developed not only for researches but to be utilized in real life. In the research, systems for environment recognition and tole-operation have been developed for task assignment and execution of biped robot as well as for human robot interaction (HRI) system. For carrying out certain tasks, an object tracking system using modified optical flow algorithm and obstacle recognition system using enhanced template matching and hierarchical support vector machine algorithm by wireless vision camera are implemented with sensor fusion system using other sensors installed in a biped walking robot. Also systems for robot manipulating and communication with user have been developed for robot.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.343-344
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• 2008

90년대에 들어서면서부터 미래원천기술 개발에 필요한 양성자원 및 중성자원의 중요성이 부각됨으로써, 이에 적합한 고에너지(수백 MeV${\sim}$수 GeV) 및 대전류(수십 mA)의 대형 양성자 가속기가 개발되어 반도체 생산, 의료장비 등 여러 분야에 널리 적용되고 있는 추세이다[1, 2]. 이에 양성자 사업단은 21세기 미래 원천기술을 개발하고 산업경쟁력을 제고하며 공공복지를 증진시킬 수 있는 양성자가속기를 개발하여, NT, BT, IT, ST등 중요 국가과학기술분야의 발전기반을 확충하기 위한 프론티어 사업목표로 하고 있으며 이에 부응할 수 있는 양성자 가속기 연구센터 건설계획을 설정하여 추진 중에 있다. 본 논문에서는 양성자가속기 연구센터 지원시설 건축설계의 일환으로 수행되고 있는 전기, 소방, 통신 및 방범설비 설계과정에서 각 설비설계시의 주요기능 및 특징에 관해 기술하고자 한다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.12
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• pp.1742-1746
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• 2014

In order to develop a overhead catenary system for the maximum speed of 400 km/h on Honam high-speed line, increasing tension of contact wire, changing dropper distributions, reducing a hard point and etc. should be considered. And it is also essential to develop core components taking account of the increased tension. Therefore we developed a new steady arm for the max. speed of 400 km/h in this study. FEM (Finite Elements Method) analysis was performed to ensure the strength of the arm. An oval shape was applied to the arm, so that 25 % of strength was increased and 9 % of weight was decreased. And a type test according to the code KRSA-3012 was performed to ensure the performance. Fatigue test in KRRI (Korea Railroad Research Institute)'s test-bed was also performed to evaluate its performance. Some section of the Honam High-speed line was constructed with the developed steady arm.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1080-1081
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• 2015

CPV system in the desert areas or areas near the equator, as is suitable for high-temperature region. As compared to silicon solar cells, CPV system have a high proportion of a BOS (balance of system). Solar cells because of its low proportion when designing a module technology is applied in a variety of ways. Applied to the CPV system is classified into two kinds of optical technology. One of those using fresnel lens uses refraction of light energy. The other is a mirror reflection of the structure using sprays. Both of these two ways to condense the sun to collect solar cell is a form of light. And goals by using a small solar cell materials is to produce more energy. This research proposes rational design approach to calculate proper system capacity in consideration of the aforementioned factors in CPV system.