• Journal of the Society of Naval Architects of Korea
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• v.43 no.1 s.145
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• pp.128-133
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• 2006

This study is focused on the skill to prevent RIB (Rigid Inflatable Boat) from sinking. For better ability to prevent sinking, single hypalon tube is replaced by double TPU (Thermoplastic Polyurethane) tube that is excellent at frictional wear strength and oil-resisting qualities. High buoyant materials are arranged in empty spaces of ship so that ship's spare buoyancy is increased. And for restoration of stable position of ship, the self-righting system is installed. Aluminium alloy is used for increasing hull strength.

• 한국체육학회지인문사회과학편
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• v.53 no.2
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• pp.531-540
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• 2014

The purpose of this study was to investigate the differences between two inflatable kayak by recording performance related variables during the kayak forward stroke motion. A total of 5 elite high school kayak players were recruited to participate while their kinematics and muscle activations were recorded while performing inside their high school swimming pool. Boat velocity, boats swaying angle, the average angular velocity and were used to evaluate the boats performance. The player's trunk rotational range of motion, knee flexion-extension angle range of motion, maximum trunk rotation angle, the knee flexion-extension angular velocity, and the upper and lower limb muscle activations were calculated and analyzed for the player's efficiency evaluation. There were no significantly different variables for the player's kinematics and their muscle activations for the two conditions. The B kayak was significantly faster than the A kaya. In addition there were no significant differences between the remaining variables for the two kayaks. In conclusion, the B kayak was faster than the A kayak, but neither of the kayaks had an influence on the player's performance variables.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.218-231
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• 2005

This paper reviews the engineering approach needed to support humans during their long-term missions in space. This approach includes closed plant production systems under microgravity or low pressure, mass recycling, air revitalization, water purification, waste management, elimination of trace contaminants, lighting, and nutrient delivery systems in controlled ecological life support system (CELSS). Requirements of crops f3r space use are high production, edibility, digestibility, many culinary uses, capability of automation, short stems, and high transpiration. Low pressure on Mars is considered to be a major obstacle for the design of greenhouses fer crop production. However interest in Mars inflatable greenhouse applicable to planetary surface has increased. Structure, internal pressure, material, method of lighting, and shielding are principal design parameters for the inflatable greenhouse. The inflatable greenhouse operating at low pressure can reduce the structural mass and atmosphere leakage rate. Plants growing at reduced pressure show an increasing transpiration rates and a high water loss. Vapor pressure increases as moisture is added to the air through transpiration or evaporation from leaks in the hydroponic system. Fluctuations in vapor pressure will significantly influence total pressure in a closed system. Thus hydroponic systems should be as tight as possible to reduce the quantity of water that evaporates from leaks. And the environmental control system to maintain high relative humidity at low pressure should be developed. The essence of technologies associated with CELSS can support human lift even at extremely harsh conditions such as in deserts, polar regions, and under the ocean on Earth as well as in space.

• Journal of Navigation and Port Research
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• v.39 no.4
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• pp.285-291
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• 2015

Exposure to cold sea water can be life-threatening to the drowned individual. Although appropriate life jacket can be usually be provided for the buoyance at the drowning accident, heat loss can make the drowned individual experience the hypothermia. Inflatable life jackets filled with inflatable air pocket can increase the thermal protection as well as the buoyancy force. Because it is important to know how the human body behaves unde the different life jacket, present study compares the thermal insulation capacity of solid type life jacket with that of inflatable life jacket. In order to represent the insulation capacity of life jacket, thermal resistance is estimated based on the assumption of steady-state. Also, a transient three-dimensional thermal distribution of the thigh is analyzed by using finite element method implementing the Pennes bioheat equation. The finite element model is a segmental, multi-layered representation of the body section which considers the heat conduction within tissue, bone, fat and local blood flow rate.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.1
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• pp.29-36
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• 2016

Tensairity girder is a light weight inflatable fabric structural concept which can be used in road emergency transportation. It uses low pressure air to stabilize compression elements against buckling. With the purpose of obtaining the comprehensive target of minimum deflection and weight under ultimate load, the cross-section and the inner pressure of tensairity girder was optimized in this paper. The Variable Complexity Modeling (VCM) method was used in this paper combining the Kriging approximate method with the Finite Element Analysis (FEA) method, which was implemented by ABAQUS. In the Kriging method, the sample points of the surrogate model were outlined by Design of Experiment (DOE) technique based on Optimal Latin Hypercube. The optimization framework was constructed in iSIGHT with a global optimization method, Multi-Island Genetic Algorithm (MIGA), followed by a local optimization method, Sequential Quadratic Program (SQP). The result of the optimization gives a prominent conceptual design of the tensairity girder, which approves the solution architecture of VCM is feasible and efficient. Furthermore, a useful trend of sensitivity between optimization variables and responses was performed to guide future design. It was proved that the inner pressure is the key parameter to balance the maximum Von Mises stress and deflection on tensairity girder, and the parameters of cross section impact the mass of tensairity girder obviously.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.2
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• pp.61-67
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• 2001

Development of a barrier system for floating debris at river is introduced. The system is to prevent pollution of coastal water caused by marine debris which originates from land. The system consists of harrier boom, mooring system and boom winder. The harrier boom, which is self-inflatable with circular band spring, guides floating debris to a collecting conveyer system. Design parameters of the harrier system were reviewed and its design criteria were established. Based on the established design criteria, a pilot harrier system was built and tested at Tanchon branch of the Han river. It is proved that the suggested system is very efficient to collect floating debris at river.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.501-512
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• 2016

We evaluated a self-inflatable osmotic tissue expander for its utility in creating sufficient soft tissue elongation for primary closure after bone grafting. Six patients with alveolar defects who required vertical augmentation of >6 mm before implant placement were enrolled. All had more than three prior surgeries, and flap advancement for primary coverage was restricted by severely fibrosed scars. Expanders were inserted beneath the flap and fixed with a screw. After 4 weeks, expander removal and bone grafting were performed simultaneously. A vertical block autograft and guided bone regeneration and distraction osteogenesis were performed. Expansion was sufficient to cover the grafted area without additional periosteal incision. Complications included mucosal perforation and displacement of the expander. All augmentation procedures healed uneventfully and the osseous implants were successfully placed. The tissue expander may facilitate primary closure by increasing soft tissue volume. In our experience, this device is effective, rapid, and minimally invasive, especially in fibrous scar tissue.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.11a
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• pp.329-331
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• 2022

국내 '수상레저기구 안전검사 기준(해양경찰청 고시)' 의 고무보트 안전검사 기준을 국제 표준 및 관련 법령(ISO-6185, 미국 ABYC 단체표준, 미국해양경비청 USCG, 뉴질랜드 해양법 NZ Maritime Law)과 비교를 통해 안정성(stability) 확보를 위하여 개선 방안을 제시하고자 한다. 현행 '수상레저기구 안전검사 기준'의 고무보트는 승선정원 13인 이상 및 특정 항해 구역에 대해서만 복원성 조건을 요구하고 있어 13인승 이하의 고무보트는 안정성 조건이 전무한 실정이다. 특히, 국제 표준 및 관련 법령과는 약 38개의 검사항목에 누락 또는 미흡한 차이가 있으며, 이에 국내 기준과 국제 표준과의 비교 분석을 통해 개인의 최소 안전을 담보 할 수 있는 고무보트의 안전성 확보 방안을 마련하고자 한다.

• The Journal of the Korea Contents Association
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• v.12 no.10
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• pp.116-127
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• 2012

With the recent rapid growth in the number of people who enjoy marine and leisure activities in Korea, the marine leisure industry faces good opportunities for development. Korean brands are in between them. In this situation, new and innovative products related to an inflatable tube, which is one of the most popular marine leisure items, will help to increase sales of domestic companies and to pioneer a new market. Research methods are largely divided into 4: investigation, analysis & synthesis, development and evaluation. This paper introduces a "tube cushion" which is an inflatable tube covered by fabrics. It can be functioned at home 365 days a year as a cushion or a children's plaything. Tactile fabrics, neoprene and air-mesh, are used as the cover with a zipper, making it easy to open and close. Moreover, by putting together tubes and connecting them with snap fastener attached straps, the cushion can be transformed into a chair, a table, a tunnel, a train, and so on, serving as a creative plaything for children. With this paper, it is expected that new and innovative items differentiated from others, like this crossover tube cushion, will help to create a 'Blue Ocean' market for the marine leisure industry from the long-term perspective.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1147-1159
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• 2018

This study focuses on the verification of a rapid protection automation system using an inflatable structure. The inflatable structure is an automatic rapid protection system against human and material damage when the subsea tunnel is flooded. Especially, it is essential for construction and operation of subsea tunnels. In this study, we have experimentally verified the rapid protection automation system using the inflatable structure designed for this problem. In order to verify this, a model tunnel with a 40: 1 reduction ratio was constructed, and air pressure of 0.1 bar and 0.15 bar was injected to divide the tunnel according to the expansion rate at 10 sec and 20 sec. According to the results of the study, the protection efficiency was better at 0.15 bar than 0.1 bar when the expansion structure was expanded, and the protection efficiency and influent control efficiency were different according to the pneumatic injection time of the inflating structure. As a result of this study, it was found that the higher the internal air pressure of the inflated structure and the faster the inflation of rate, the more effectively the inflated structure was inflated. As a result of this study, it is necessary to further study the wedge type structure which is useful for the storage method of expansion structure, shape and expansion derivative, inhibition of expansion structure during protection and control of inflow water.