• Journal of environmental and Sanitary engineering
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• v.10 no.3
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• pp.124-130
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• 1995

Air pollution problem by air craft was reviewed from emission gas components from air craft and pollutants amount generated in airport with the compareness of domestic transportation data by airplane and foreign data. It is reported that concentration of emission gas from air craft is lower than that of pollutants from automobile and factory. But transportation frequency is increasing rapidly in Korea. It is recommended that concerns should be taken on long- term of counterplan device about it.

• Journal of Navigation and Port Research
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• v.36 no.3
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• pp.157-162
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• 2012

A planing craft is designed specifically to achieve comparatively high speed on the surface of the water. The frictional resistance of planing craft can be reduced further by injecting air to the craft's bottom. In this paper, the resistance characteristics of high speed planing crafts with & without air injection at the bottom were compared by sea model-test method. As a result, we conformed that planing craft with air injection has much greater the effect of resistance reduction.

• Journal of the Korea Institute of Military Science and Technology
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• v.3 no.1
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• pp.66-75
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• 2000

The purpose of this study is to develop and illustrate methods of applying trade-off techniques to landing craft air cushion design evaluation. The problem areas of concern are the application of quantitative analytical methods to conceptual design. The interrelationships between composite system measures and selected performance requirements(speed, cruising range, cargo etc.) are analyzed and the expressions for gross weight are developed as functions of performance parameters. Trade-offs of performance parameters in terms of weight are then calculated. The application of these results to evaluation of Require Operational Capabilities are illustrated.

• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.177-185
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• 2011

Craft industry in Iran in the past to preserve the technology and production methods, or a newly developed in modern technology, techniques, and material that are intended to use in the decorative, practical characteristics, and the general public are using living water district, ornaments, symbols, products, and so on are collectively, craft industry-specific regional environmental, air velocity, ruins, etc. based on the characteristics of the region's traditional or artistic nature to produce products with the industry, the craft inherent in cultural element out of the help of stock, production, distribution and consumption of a series of process, namely the commercialization of the craft. This future-oriented State images for a unique sentiment based on the tradition of craft culture prize of Korea national image to create a decisive role in the would do. Therefore, in this study, consumers of the craft cultural products awareness and marketability to domestic craft industry status and enhance the use of the show. In addition, based on craft culture industry's efficiency and the issue is what the research and improvement.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.5
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• pp.697-702
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• 2010

A WIG(Wing-In-Ground effect) craft flies close to the water surface by utilizing a cushion of relatively high pressurized air between its wing and water surface. This implies that when one designs such craft it is important to have lightweight structures with adequate strength to resist external loads with some margins. To investigate this requirement, this paper deals with the structural analysis of the bottom plate of small WIG craft having a design landing weight of 1.2-ton. As building materials for the WIG craft, pre-preg carbon/epoxy composites are considered. The strength information of the bottom plate is obtained using the first-ply-failure analysis in conjunction with a mid-plane symmetric laminated plate theory. As a result, the first-ply-failure location, load and deflection of the bottom plate are obtained. The calculated strength information is compared with the water reaction load for the bottom plate of seaplanes considered when they land on the water surface -the same fluid-structure interaction mechanism as that of WIG craft. In the calculation of seaplane water reaction load information, the rules shown in FAR(Federal Aviation Regulations) Part 25 are used. Through the comparison, the structural integrity of the bottom plate for the WIG craft is checked.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.40-50
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• 2018

Today, the development of industries and rapid urbanization has a profound impact on the human environment. It can be said that the environment in the craft village is most affected. The environment in these areas is severely degraded and depending on the type of production, the environment in the craft villages is different. In Phong Khe ward of Bac Ninh Province, Vietnam, there are over 204 small and large facilities of recycling and producing paper. The paper facilities produce about 200,000 tons of paper each year and the amount of paper produced is not less than 500 tons each day in Phong Khe. They are creating livelihoods for more than 6,000 workers and generating local budgets from VND- 50 billion to VND 60 billion per year. Despite this great contribution, the use of old machines and "backward" modes of production means that paper recycling has caused serious air, soil, and water pollution in the region. The specific objectives of this study were as follows: (1) provide an overview of paper production process in the Phong Khe paper craft village; (2) comprehensive literature review of the current status of water environment, atmosphere environment, soil environment and solid waste; (3) figure out about waste treatment in Phong Khe ward.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.2
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• pp.241-249
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• 2008

In this study, lateral vibration analysis has been conducted on a propulsion and lift shafting system for an air cushion vehicle using ANSYS code. The shafting system is totally flexible multi-elements system including air propeller, aluminum alloy of lift fan and thin walled shaft with flexible coupling. The analysis included the lateral natural frequencies, mode shapes and harmonic analysis of the shafting system taking into account three-dimensional models for propulsion and lifting shaft system. In case of ACV the yawing and pitching rate of craft will be quite high. During yawing and pitching of craft significant gyroscopic moment will be applied to the shafting and will generate high amplitude of lateral vibration. So, such a shafting system has very intricate lateral vibrating characteristics and natural frequencies of shafting must be avoided in the range of operating revolution. The control of lateral vibration is included in this study.

• International Journal of Naval Architecture and Ocean Engineering
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• v.4 no.4
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• pp.460-476
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• 2012

High-speed crafts suffer from losing a huge amount of their machinery energy in the form of heat loss with the exhaust gases. This will surely increase the annual operating cost of this type of ships and an adverse effect on the environment. This paper introduces a suggestion that may contribute to overcoming such problems. It presents the possibility of reusing the energy lost by the ships' exhaust gases as heating source for an absorption air condition unit onboard high-speed crafts. As a numerical example; the proposed method was investigated at a high-speed craft operating in Red Sea between Egypt and the Kingdom of Saudi Arabia. The results obtained are very satisfactory. It showed the possibility of providing the required ship's air condition cooling load during sailing and in port. Economically, this will reduce the annual ship's operating cost. Moreover, it will achieve a valuable reduction of ship's emissions.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.3
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• pp.36-42
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• 2000

A fundamental experimental study for an alternative proposal to super-speed craft propulsion system called underwater ram-jet propulsion by high pressure air ejection as driving force was investigated. For basic study of the effects of ram-jet propulsion performance, a simple underwater ram-jet flow field was established and PIV(Particle Image Velocimetry) method was adopted to analyse the jet-induced flow appearing at ram intake, mixing chamber and nozzle. Some flow dynamics relating to the high-speed ram-jet effect were discussed for the basic understanding of the its propulsion principle.

• Journal of radiological science and technology
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• v.41 no.6
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• pp.643-649
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• 2018

Recently, together with advancement of domestic aviation industry, overseas tourists using planes have been soared. This study aimed to investigate the risk of diseases for the passengers and flight attendants from the exposed cosmic radiation during the flight by domestic and international literature reviews, as follows. Airliners should develop the program to measure the actual radiation dose and prepare the portable devices for radiation measurement in flight to lower the accumulated dose of cosmic radiation by the attendants. Regulation should be prepared to check the exposed dose during the flight for the passengers by announcement of individual exposed radiation dose which has been provided only to the flight attendants. Passengers and flight attendants should recognize they are exposed to excessive cosmic radiation during the flight and civilians should be protected by the cosmic radiation when they use the flights, which should be prepared by the regulations.