• Journal of Advanced Marine Engineering and Technology
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• v.17 no.3
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• pp.42-49
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• 1993

Recently, because the lubricating oil showed a tendency to be emulsified and oxidized by high speed, high output and the extension of maintenance & conservation of marine engine, the cavitation erosion-corrosion at such an environment became a big problem on effective performance of engine. Therefore, there was a need to study the behavior and protection of erosion-corrosion damage, and then applied inhibitor to a protective method of cavitation erosion- corrosion damage. At this time, test environments were marine lubricating oil & various emulsified oil that mixed distilled water and sea water etc., and also used 20KHz, 24.mu.m piezoelectric vibrator as an experimental apparatus of cavitation erosion. With this apparatus, we investigated an influence of the emulsified oil on characteristics of erosion-corrosion and protection for erosion-corrosion by inhibitor at slide bearing metals.

• ETRI Journal
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• v.32 no.5
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• pp.646-656
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• 2010

A component is a reusable and replaceable software module accessed through its interface. Component-based development is expected to shorten the development period, reduce maintenance costs, and improve program reusability and the interoperability of components. This paper proposes a new robot software component platform in order to support the entire process of robot software development. It consists of specifications of a component model, component authoring tool, component composer, and component execution engine. To show its feasibility, this paper presents the analysis results of the component's communication overhead, a comparison with other robotic software platforms, and applications in commercial robots.

• Journal of Energy Engineering
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• v.24 no.3
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• pp.34-39
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• 2015

Recently, Air pollution is gradually increasing which are coming from the exhaust of the ICE vehicles in the world. ICE vehicle exhaust gas and $CO_2$ are widely suspected of contributing to the called greenhouse effect, fueling fears of global warming. Therefore, many countries are striving to decrease the vehicle exhaust gas and have developed a variety of policies as air pollution regulation plans. To comply with the regulations, automotive industry has developed hybrid vehicles, which have features of both ICE vehicles and electric vehicles. Hybrid car is eco-friendly and has lowered exhausting gases and improved fuel efficiency. This research has been written to show that break down cases with EGR valve in hybrid cars, steadily increasing in use, and to help with on-site maintenance.

• Journal of Navigation and Port Research
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• v.39 no.2
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• pp.83-88
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• 2015

Korea has a systemic problem with lack of engine maintenance, especially among the Commercial Fishing Vessel fleet. This results in a inordinate percent of SAR call-outs for vessels with engine failure. These SAR call-outs lead to a free tow to shore by KCG or by one of its volunteer associates. Although these tows are not a terrible economic burden on KCG, it is a burden in terms of time and resources mis-allocated. This paper proposes a Commercial Fishing Vessel Examination (CFVE) program modeled after the program run by USCG. It is expected that adopting the CFVE program, KCG may be able to create a culture of safety among fishermen; thus, replicating the USCG's success rates.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.2
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• pp.253-259
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• 2006

There is few study which automatically diagnoses the fault from ship's monitored data. The bigger control and monitoring system is. the more important fault diagnosis and maintenance is to reduce damage caused by system fault. This paper proposes fault diagnosis system using a correlation analysis algorithm which is able to diagnose and forecast the fault from monitored data and is composed of fault detection knowledge base and fault diagnosis knowledge base. For all kinds of ship's engine room monitored data are classified with combustion subsystem, heat exchange subsystem and electric motor and pump subsystem, To verify capability of fault detection, diagnosis and prediction, FMS(Fault Management System) is developed by C++. Simulation by FMS is carried out with population data set made by the log book data of 2 months duration from a large full container ship of H shipping company.

• Journal of the Korea Society for Simulation
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• v.9 no.1
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• pp.1-9
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• 2000

When a new manufacturing line is constructed, its production capacity can be substantially affected in its design stage. Computer simulation often provides better design by evaluating feasible alternatives. In this paper we study an automobile engine manufacturing line which is under construction. Three alternatives are considered in the design; (1) to use machining tools of longer life; (2) to reassign the buffer space to each sequential processes while maintaining the same total buffer length; and (3) to reduce the machine repair time to 30 minutes using TPM and maintenance team. Simulation results using AutoMod indicates that employing the three alternatives will save about 1.5 million dollars per year.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.251-256
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• 2005

There is few study which automatically diagnose the fault from ship's monitored signal. The bigger control and monitoring system is, the more important fault diagnosis and maintenance is to reduce damage brought forth by system fault. This paper proposes fault diagnosis system using a correlation analysis algorithm which is able to diagnose and forecast the fault and is composed to fault detection knowledge base and fault diagnosis knowledge base. For this all kinds of ship's engine room monitored data are classified with combustion subsystem, heat exchange subsystem and electric motor and pump subsystem by analyzing ship's operation data. To verifying capability of fault detection, diagnosis and prediction, Fault Management System(FMS) is developed by C++. Simulation experiment by FMS is carried out with population data set made by log book data of 2 months duration from a large full container ship of H shipping company.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.155-161
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• 2005

Governors control the revolution speed of heat engines such as diesel engines, steam turbines and gas turbines. Precise and prompt tests for the control performances of governors are essential both in governors' manufacturing processes and in governors' maintenance processes. In the conventional governor test systems controlled by analog type electronic controllers, the incorporation of heat engine's dynamics to the test system have been considered very difficult to realize. This study suggests a new governor test system controlled by a digital controller using a personal computer. The application of the digital controller to the test system instead of the analog type electronic controller have brought about the following advancements; (1) heat engine's dynamics could be implemented easily in the test system, (2) automatic test data acquisition both in steady state and in transient state enables us to save test time and to enhance the reliability of the tests.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.15 no.3
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• pp.70-76
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• 2007

The benefits for using reduced takeoff thrust are many, ranging from lower maintenance and operating costs to improved engine and dispatch reliabilities. Some pilots, however, are apprehensive about using reduced thrust. They are particularly reluctant to use the maximum permissible level of reduced thrust. Two common arguments are (1)If reduced thrust is used, then the airplane will not be able to clear the obstacles if an engine fails during takeoff, and (2)If the maximum allowable assumed temperature is used, then there will be no stopping margin left if the takeoff is aborted. There is the notion that using reduced thrust sacrifices safety. The intent of this discussion is to: (1)Show that reduced thrust performance meets all regulatory requirements (2)Show that the Assumed Temperature method includes inherent extra performance margins (3)Show how to maximize performance margins while maximizing thrust reduction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.365-373
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• 2002

For gas turbine engines, the safe life methodology has historically been used fur fatigue life management of failure critical engine components. The safe retirement limit is necessarily determined by a conservative life evaluation procedure, thereby many components which have a long residual life are discarded. The objective of this study is to introduce the damage tolerant design concept into the life management for aircraft engine component instead of conservative fatigue life methodology which has been used for both design and maintenance. Crack growth data were collected on a nickel base superalloy which have been subjected to combined static and cyclic loading at elevated temperatures. Stress analysis fur turbine disk was carried out. The program for computing creep-fatigue crack growth was developed. The residual lifes of turbine disk component under various temperatures and conditions using creep-fatigue crack growth data were estimated. As the result of analysis, it was confirmed that retirement fur cause concept was applicable to the evaluation of residual life of retired turbine disk which had been designed based on the conventional fatigue life methodology.