• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 춘계학술발표회
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• pp.17-22
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• 2003

With the terrorist attacks on 11 September 2001, the ships and their crews' safety and security have become a major issue in the maritime industries. In high-risk terrorism. not only ship owners and port authorities but also crew members on board should take precautions in the conduct of their business. In this paper, the vulnerability and essential elements in overall security of merchant ship are analyzed with a discussion in depth of the concept and principles of maritime security management. Author proposes ship's security model to reduce security risk and to minimize damage as a basic study for designing security system for merchant ship.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.160-163
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• 2008

Currently workmen take charge of the maintenance work of bridges. But the process of sealing cracks in damage bridge is dangerous, costly, and labor-intensive operation Labor turnover and training are increasing problems related to crack sealing crews, and as traffic volumes increase, crack sealing operations become increasingly disruptive to the general public. Automation crack sealing can reduce labor and road user costs, improve work quality and decrease worker exposure to bridge hazards. This research aims to develop an automated damage bridge crack sealing system and developing of algorithms for hybrid controlling.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.10-11
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• 2006

The fault location is obtained from the distance relay that detects the fault of the transmission line. In this time, transmission line crews track down the fault location and the reasons. However, because of having error at the fault location of the distance relay, there is a discordance between real and obtained fault location. As this reason, the inspection time for finding fault location can be longer. In this paper, we proposed the statistical (regression) analysis method based on each type of relay's the historical fault location data and the real fault distance data to improve the problems. With finding the regression equation based on the regression analysis, and putting the relay fault location into that equation, the real fault distance is calculated. As a result of the Prediction fault location, the inspection time of transmission line can be reduced.

• 한국철도학회논문집
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• 제9권2호
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• pp.206-211
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• 2006

This thesis presents railroad crew restoring problem, which is to determine the railroad plan allocation. This problem is constructed that determine the sequence of duties that railroad crews have to perform. We analyze characteristic of this problem and railroad industry. It's hard to consider many constraint conditions. We propose Integer Programming model and easy methodology to be considered all given operation rules. This problem is known to be NP-hard. We develop a genetic algorithm, which is proved to be powerful in solving optimization problems. We proposed the effective mathematical model and algorithm about making crew restoring in real industry.

• 연구논문집
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• 통권29호
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• pp.83-90
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• 1999

In naval ships, pump machineries are the major sources of airborne and structure-borne noise. Noise is critical issue in ships not only it causes annoyance to crews, but also it can increase the underwater radiated noise, which is crucial in anti-submarine warfare. In present study, it is discussed the reduction of structure-borne noise of pump machineries by showing several examples. The most typical and effective solution is to use double resilient mount system. However, in cases where double resilient system cannot be applied due to space and weight increase, rubber pad can be used to reduce the structure-borne noise. In principle, the concept of structure-borne noise reduction is the same as that of vibration isolation.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.186-193
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• 2004

As a point that should be improved further in present SART, the size, the number, and the economy were enumerated. Some SART developed to solve them in Japan were introduced in this paper. That is automatically operating SART, circular polarization SART and so on. In addition, One Mile SART was mentioned. It is SART miniaturized instead of limiting the function, because all crews and passengers can always carry the small and light SART. The parts were made for trial purposes and the performance was confirmed.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.133-134
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• 2006

Recently, despite of the effects of international Coordination and cooperation to prevent piracy, piracy is on an increasing trend every year. Such circumstances may have a bad effect on the sound development of world economy by means of trade in sea as well as treat to the safety of crews and safe operation of ships. Finally, Modern maritime piracy has become one of the major threats to safety at sea. We having Cargo-owners or Ship-owners attacked by piracy, it causes enormous economic losses. Therefore, Ship-owners and Cargo-owners insure Cargo Insurance, Hull Insurance and P&I Insurance to indemnity of losses which is caused by piracy. The Purpose of this paper was to explain the losses caused by piracy and studying the limits of the possibility of indemnity in the Cargo Insurance, Hull Insurance and P&I Insurance.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.149-154
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• 2001

Ship owners are demanding quieter vessels since crews have become more sensitive to their acoustic environment. Accordingly, designers of shipyards need to respond intelligently to the challenging requirements of delivering a quiet vessel. In early design stage, to predict shipboard noise the statistical approach is preferred to other methods because of simplicity. However, since the noise characteristics of the ships vary continuously with the environments, it is necessary to update the prediction formula with data base management system. This paper describes the feature of database program with the prediction method. Database management programs with GUI, are applied to Intranet system that is accessible by any users. Statistical approach to the prediction of A-weighted noise level in ship cabins, based on multiple regression analysis, is conducted. The noise levels in ship cabins are mainly affected by the parameters of the deadweight, the type of ship, the relative location of engines and cabins, the type of deckhouse, etc. As a result of verification, the formulas ensure the accuracy of 3 ㏈ in 83 % of cabins.

• 한국소음진동공학회논문집
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• 제25권5호
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• pp.337-344
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• 2015

As many of armored vehicles are seriously exposed to threat of IEDs(Improvised Explosive Devices) in the Afghanistan war and the Iraq war. V-shaped military vehicles are deeply studied in order to protect crews and mounted soldiers against land mines. Generally the experiment on full-scaled V-shaped structure needs excessively high cost, which becomes a huge barrier to study. In this paper, we explore the possibility to make a half-scaled model of the V-shaped structure by using the geometric similarity scaling. We demonstrate the geometric similarity scaling between the original model and the half-scaled model is established on the momentum and deflections of structure via computer simulations and experiments. At this stage, we conduct only numerical analysis of predicting vibration of V-shaped structure because measuring vibration of structure is difficult in the mass-explosion experiment, which is remained as future work.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.86-92
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• 2000

The crew operation scheduling problem is divided into duty generation and duty allocation. The railway crew roster scheduling(duty allocation) is developed monthly for each crew's office, considering the car types and crew's driving ability. However, it is very difficult to make schedules which assign monthly working hours to each crew evenly. The purpose of this thesis is to minimize the differences between each crew's total duty times and make a rostering table. To minimize the differences among monthly working hours of each crews are grouped according to car type and crew's driving ability and a rostering table which could be shared by the group members is developed. Our approach is to apply the techniques of Constraint Programming in order to solve such problems efficiently. This algorithm is suitable to solve optimization problems which involve many complicated constraints. And including the concept of cost, we suggested the model which enable to make the rostering table with a minimum personnel.