• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.208-211
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• 2005

This paper describes the development process of steering system for reduce idle vibration through the data level of frequency and sensitivity. High stiffness and light weight vehicle is a major target in the refinement of passenger cars to meet customers' contradictable requirements between NVH performance and fuel economy. The target frequency of the steering system is set by benchmarking of a competitive vehicle and the vibration mode map is used to separate steering column modes from resonance of body structure and engine idle rpm. This paper descirbes the analysis approach process for high stiffness of steering system and the design guideline is suggested about steering column and support system by using mother car at initial design stage. We used a patent map in order to analyze accurately a technical trend and suggested the design process using dynamic damper of steering system considering sensitivity. And we established techniques of analysis on steering system and evaluated the level of accuracy of analysis through correlating the test and analysis results. It makes possible to design the good NVH performance vehicle at initial design stage and save vehicles to be used in tests. These improvements can lead to shortening the time needed to develop better vehicles.

• Journal of Korea Port Economic Association
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• v.17 no.2
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• pp.1-28
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• 2001

Korea has been at the forefront of efforts to enhance international cooperation in transport and communications within Northeast Asia. This effort is driven not only by the benefits that could accrue to the Korean Peninsula but also to all nations in the region. Mutual cooperation within Northeast Asia would reduce transport and communications costs and provide the basis for a regional transport and logistics network. Before progress can be made towards an integrated transport and communications system in Northeast Asia, however, there is a need to evaluate its prospects, outline a visionary plan, and detail a preferred strategy. The strategy to develop the Korean Peninsula as the gateway for Northeast Asia should harmonize with the region's common transport (and communications) policy The strategy adopted by South Korea is focused primarily on the development of an improved logistics infrastructure that would be extended to North Korea upon reunification. The seaport and airport developments In Korea will have to be supported by improved access to planned high-speed railways, expressways and freight distribution centers that, in turn, are to be integrated with new telecommunications and computer technologies. The benefits from these improvements will be lost unless existing government monopolies controlling seaport, airport, rail, road and expressway developments are commercialized to ensure that the price of transport reflects its actual cost. Technical harmonization between different modes should be promoted to facilitate efficient intermodal transport between the Korean Peninsula and the rest of Northeast Asia.

• Advances in pediatric surgery
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• v.9 no.2
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• pp.77-80
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• 2003

Continuous Ambulatory Peritoneal Dialysis (CAPD) has now become an established form of renal replacement therapy in children. Despite of technical improvements, there are various complications in CAPD. We reviewed medical records of children who received CAPD at Seoul National University Children's Hospital in the period between May 1991 and June 2002. Ninety-three procedures of CAPD catheter insertion in 70 patients were included in this study. Complication rate was 64.5%, and CAPD catheter related peritonitis was most common. In conclusion, CAPD catheter related peritonitis develops in considerable number of pediatric patients. Although the peritonitis could be treated with empirical antibiotics therapy, further investigation to prevent complication is required.

• Advances in Automotive Engineering
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• v.1 no.1
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• pp.1-20
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• 2018

The aim of this study is the optimization of the parameters of interconnected Hydro-Pneumatic (HP) suspension system of a three-axle vehicle for ride comfort and handling. For HP suspension systems of equivalent vertical stiffness and damping characteristics, interconnected HP suspension systems increase roll and pitch stiffness and damping characteristics of the vehicle as compared to unconnected HP suspension systems. Thus, they result in improved handling and braking/acceleration performances of the vehicle. However, increased roll and pitch stiffness and damping characteristics also increase roll and pitch accelerations, which in turn result in degraded ride comfort performance. Therefore, in order to improve both ride comfort and vehicle handling performances simultaneously, an optimum parameter set of an interconnected HP suspension system is obtained through an optimization procedure. The objective function is formed as the sum of the weighted vertical accelerations according to ISO 2631. The roll angle, one of the important measures of vehicle handling and driving safety, is imposed as a constraint in the optimization study. Upper and lower parameter bounds are used in the optimization in order to get a physically realizable parameter set. Optimization procedure is implemented for a three-axle vehicle with unconnected and interconnected suspension systems separately. Optimization results show that interconnected HP suspension system results in improvements in both ride comfort and vehicle handling performance, as compared to the unconnected suspension system. As a result, interconnected HP suspension systems present a solution to the conflict between ride comfort and vehicle handling which is present in unconnected suspension systems.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.33-38
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• 2002

A country is acutely needed to establish a marine salvage & oil spills response in order to prepare for a large accidents. Although our country depends on a foreign technique when a large marine accidents occur, insufficiency of facilities and technique. With these problems, because of the damage of accidents expands due to not taking proper actions, Accordingly, in case of marine accidents, this paper will suggest a various scheme of infrastructure in salvage & oil spills response system in order for quick and effective salvage & oil spills response, investment of facilities, technical development of salvage & oil spills response, and improvement of ability etc

• Journal of Navigation and Port Research
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• v.34 no.9
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• pp.699-704
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• 2010

Recently, the navigation risk is increasing significantly with growing of vessels' volume and propelling marine facilities, water bridges and port development etc. As a result, Ministry of Land, Transport and Maritime Affairs enacted a new law called MSA(Maritime Safety Audit) as a comprehensive maritime traffic safety management scheme in order to ensure safety improvements from the early planning stage to post managing of the development which affect the maritime traffic environment. MSA as a tool for improving maritime traffic safety is a formal safety diagnosis assessment in the existing or future ship's fairway by an independent audit institute. It examines the potential hazards of maritime traffic safety about the port development, if necessary, and is to ensure the implementation of appropriate safety measures. The primary purpose of MSA is to identify potential risk elements affecting safe navigation. This paper is aimed to introduce the backgrounds, the necessity and efficiency of MSA and also to describe some technical standards and diagnostic procedures.

• Tunnel and Underground Space
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• v.21 no.6
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• pp.427-438
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• 2011

Segment lining is a key permanent lining structure to maintain the shield tunnel stability in shield tunnel operation. Moreover, segment lining generally accounts for the largest proportion in the shield tunnel construction costs. As a result, technical improvements to increase its economic feasibility have been actively carried out. This study aims to propose the development directions of high-performance segments from their recent cutting technologies. In addition, based on over 2,100 world-widely collected segment design data, a series of statistical analyses of segment key design parameters such as thickness, width and the number of divisions as well as segment materials were carried out to approximately estimate them in a design stage.

• Journal of the Society of Disaster Information
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• v.11 no.2
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• pp.269-278
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• 2015

Developed a service platform technology for automated that analyze the fire-fighting vulnerable area and equipped a map online. As a result, it is possible to provide the information necessary for the vulnerable area of the fire-fighting activity online. If progress on the study of the utilized service, it is possible to reduce the Golden Time of the fire fighting field. In this study, Confirmed the technical viability satisfactory to the management and service expansion improvements to fire-fighting vulnerable area.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1886-1891
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• 1998

Traction battery chargers are an integral part of the required charging infrastructure. EV charging systems are continuing to improve in design. The newer types are affecting power quality to a much lesser extent. High efficiency battery chargers are being designed and produced which form little or no harmonic distortion. In addition chargers are becoming smaller and lighter. This is due mainly to the fact that there are improvements in the power electronics industry, especially with respected to IGBTs. Lower costs are achieved by the reduction in price of the IGBTs, standard magnetic material and small cores for inductors and transformers. But electric vehicles occupy a relatively small market niche at present. Therefore with already existing power supply networks, establishment of EV infrastructure can safeguard the service value of present vehicle as well as ensure the ability to charge a significant number of such vehicle. In this paper, we surveyed the update charging technologies according to the conductive charging, inductive charging and fast charging. Then we suggested cost-optimized charging infrastructure in consideration of the economical, political and technical standpoint.

• Journal of Arbitration Studies
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• v.28 no.2
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• pp.249-275
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• 2018

Today's Internet environment is growing rapidly, and transactions based on it are also rapidly increasing. E-commerce allows merchants and consumers in different countries to easily trade goods across borders. However, the increase in international consumer transactions through the Internet is accompanied by an increase in disputes. International consumer transactions are characterized by a distinction among long distance, small sum, and different jurisdictions. International consumer transactions cannot be solved only by way of resolving disputes in past international transactions. The best way to resolve disputes between international carriers and consumers is through the Internet. In this regard, UNCITRAL has been preparing to enact legislation on ODR as a solution to international electronic trade disputes and, as a result, UNCITRAL adopted guidelines for operating the ODR procedure for building the ODR platform. The European Union has also increased its disputes in the European Union, which is active in the intra-regional market. Institutional improvements were made to solve this problem; therefore, the European Union (EU) has enacted the ODR Regulations for EU consumer disputes. Based on such, this study constructed the ODR platform, which is used as a way to resolve consumer disputes in the regional market.