• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.77-84
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• 2003

The excessive cost of building ships causes the instability of payability, which manage poorly fishing vessels longer than 24m. As a result, an officer evades embarkation and a vicious circle is repeated. In this study, the optimal engine horsepower system for fishing vessels longer than 24m was invented to develop the most efficient engine horsepower, and also a database program for the most efficient engine horsepower has been developed based on the type of and their size.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.3
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• pp.3-10
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• 1993

The main propulsion system may be the most complicated of the shipboard systems. Many factors such as fuel economy, weight, space, first cost, reliability, vibration and noise must be considered when selecting the prime mover of the main propulsion system for ships. An expert system is a computer program that represents and reasons with knowledge of some specialist subject with a view to solving problems or giving advice. Recently, it is being developed increasingly with wider applications in many industries. This paper describes development of knowledge-based system for main engine selection of ships using general purpose expert system development tool, Nexpert Object. Developed system is consist of ship performance estimation module such as resistance and propulsion, data base for main engine, knowledge base for main engine selection in Nexpert Object and graphic user interface.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.4
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• pp.1-7
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• 1993

This paper describes development of a knowledge-based system for main engine selection of ships using general purpose expert system development tool, Nexpert Object. Developed system consist of ship performance estimation module such as resistance and propulsion, data base for main engine, knowledge base for main engine selection in Nexpert Object and graphic user interface.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.107-114
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• 2006

Material selection is one of the important activities in design and manufacturing. A selected material at the conceptual design stage affects functionality of the designed part as well as manufacturability and cost of the final product. Unfortunately there are not many accessible material databases that can be used for design. In this research, a web-based material database was constructed. In order to assist designers to compare different materials, two-dimensional and three-dimensional graphs were provided via the web browser Using these graphical tools, multi-dimensional comparison was available in more intuitive manner. As a case study, this system was applied for material selection of an automotive engine pulley.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.1
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• pp.85-91
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• 2005

The existing fisheries managers ignored the fishery environment changes, have built competitively vessels of efficiency superiority with related corporations, and have captured indisciminately fisheries resourecs. The economical engine horsepower selection model for fishing vessels shorter than 24m is developed. Also, the economical engine horsepower selection model system is verified by the existing vessels, and the optimum vessel scale and engine horsepower classified by the type of fishery and scale are proposed.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.5
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• pp.283-289
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• 2003

This paper proposes an expert system which can determine automatically the shunting routes corresponding to the given shunting works by considering totally the train operating environments in the station. The expert system proposes the multiple shunting routes with priority of selection based on heuristic search strategy. Accordingly, system operator can select a shunting route with the safety and efficiency among the those shunting routes. The expert system consists of a main inference engine and a sub inference engine. The main inference engine determines the shunting routes with selection priority using the segment routes obtained from the sub inference engine. The heuristic rules are extracted from operating knowledges of the veteran route operator and station topology. It is implemented in C computer language for the purpose of the implementation of the inference engine using the dynamic memory allocation technique. And, the validity of the builted expert system is proved by a test case for the model station.

• Advances in aircraft and spacecraft science
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• v.9 no.5
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• pp.401-414
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• 2022

In the present paper, the optimal selection of batteries for an electric pump-fed hybrid rocket engine is analyzed. A two-stage Mars Ascent Vehicle, suitable for the Mars Sample Return Mission, is considered as test case. A single engine is employed in the second stage, whereas the first stage uses a cluster of two engines. The initial mass of the launcher is equal to 500 kg and the same hybrid rocket engine is considered for both stages. Ragone plot-based correlations are embedded in the optimization process in order to chose the optimal values of specific energy and specific power, which minimize the battery mass ad hoc for the optimized engine design and ascent trajectory. Results show that a payload close to 100 kg is achievable considering the current commercial battery technology.

• Journal of Korea Society of Industrial Information Systems
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• v.4 no.4
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• pp.100-110
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• 1999

The decision method for the selection of search engine and the number of returned documents for meta search engine proposed in this paper could provide a solution to reduce network traffic and to maintain the precision ratio. The experiments are performed to evaluate the proposed scheme using currently popular search engines and most frequently used queries.

• International journal of advanced smart convergence
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• v.11 no.3
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• pp.150-156
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• 2022

Recently, the use of Unreal Engine for animation production is increasing. In this situation, Unreal Engine's 'MetaHuman Creator' helps make it easier to apply realistic characters to animation. In this regard, we tried to produce animations using 'MetaHuman' and verify the effectiveness and differences from the animation production process using only Maya software. To increase the efficiency of the production process, the animation process was made with Maya software. We tried to import animation data from Unreal Engine and go through the process of making animations, and try to find out if there are any problems. And we tried to compare animations made with realistic 'MetaHuman' characters and animation works using cartoon-type characters. The use of the same camera lens in realistic character animations and cartoon character animations produced based on the same scenario was judged to be the cause of the lack of realistic animation screen composition. The analysis revealed that a different approach from the existing animation camera lens selection is required for the selection of the camera lens in the production of realistic animation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.481-487
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• 1997

The development of transportation and construction equipment has required higher engine power and lower operation cost. The sound which the engine emits often degrade the performance of the whole system which adopts that engine. Specially the marine engine requires high restriction on the noise level for the customer's comfort and safety. The noise and vibration of Diesel engine must be carefully considered in the early design step. The double antivibration system is effective to increase the efficiency of antivibration, and the acoustic enclosure for reducing the noise level. 2 DOF model was effective to estimate the antivibration performance, which allows to determine the mass of the engine bed and the specification of the engine mount. The mass distribution of the enclosure system can be considered effectively by using the FEM model. The design contains structurally rigid engine bed by FEM, which is for reducing the influence of the flexible vibration, rubber mount selection as well as the acoustic enclosure design.