• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.285-288
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• 2006

Recently, polymer mortar has been developed not only more improving the performance of modified mortar with polymer, but also protecting and repairing materials of structures, especially in marine environment because of their excellent performance to improve compressive strength, flexural strength, and adhesive strength. however, in fact, these rehabilitation techniques in marine environment, which consist of removing delaminated areas of concrete, cleaning affected steel and patching with polymer mortar, have proven to be ineffective for marine structures. Also, repairs are often repeated every several years. Therefore, it is neccessary to research performance evalution of chloride ion penetration of polymar mortar for section restoration.

• Proceedings of the Korean Society of Radiological Science
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• 1995.05a
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• pp.132-133
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• 1995

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.1
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• pp.75-81
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• 2000

To provide the appropriate direction for development of transient control in a gasoline engine, transient performance analysis and evalution under four accelerating types based on typical driver's acceleration type were implemented by experimental study. In order to evaluate the characteristics of transient performance quanititatively, the concept and method by transient response specifications were introduced. Several performance parameters in terms of engine speed(RPM), manifold absolute pressure(MAP), fuel injection duration($\DeltatI_{nj}$) and air excess ratio($\lambda$) were emasured simultaneously during the four types of the throttle valve opening with the step motor controlled by PC. The result showed that transient response specifications in terms of delay time, rising time and settling time characterized the transient performance for four acceleration types quantitatively. Intensified acceleration type was most economical and linear acceleration type revealed the best emission performance.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.201-215
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• 2003

At present, European railways in U.K., Sweden, and Belgium have taken serious efforts to improve railway services by implementing a service evaluation system. Not only do they measure the service-related performance of a railway system, but also operate an incentive system according to the results of service-related performance. This performance evaluation system can be also used to provide basic data for other policies such as fares, subsidies and track user charges etc. After the restructuring process of Korean national railways, therefore, although it is expected to face many difficulties in the future, it is desirable to implement a performance evaluation system for securing the long-term growth of Korean railway industry.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.3
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• pp.265-271
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• 1997

A fuzzy logic controller (FLC) has been widely used for many applications in recent years. But the relationship between control performance and design parameters has not been handled explicity in the conventional theory of fuzzy logic control. In this paper, based on the similarity between an FLC and a variable structure control (VSC) theory, a performance evaluation of an FLC, which gives quantitative accounts on the relationship is presented. The validity of the analysis is verified through extensive computer simulations.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.6 no.1
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• pp.65-71
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• 2010

The plugging rate of reheater tubes of Wolsung unit 1 nuclear power plant has been increased by corrosion and erosion since 1990. As the dimensions of the new first stage reheater bundle tubes which were supplied by Hanjung company to replace were different from old one, numerical calculations are carried out for flow and heat transfer in the reheater bundle tubes of the N.P.P. Numerical calculations consists of thermal performance, drain line pressure drop, flow change by pressure drop of line, stress analysis of finned tubes and analysis of flow induced vibration. Computational analysis using heat transfer research institute program is adopted to verify the results of the numerical calculations. It contains the evalution of performance in the system with view to location of the new reheater bundle and it shows the differences between the numerical calculation results and heat transfer research institute program output.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.8
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• pp.92-98
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• 1995

The position control of flexible joint manipulator is investigated by applying the self-organizing fuzzy logic controller (SOC) proposed by Procyk and Mamdani. The SOC is a heuristic rule-based controller and a further extension of an ordinary fuzzy controller, which has a hierachy structrue which consists of an algorithm being identical to a fuzzy controller at the lower ollp and a learning algorithm accomodating the performance evalution and rule modification function at the upper ollp. This form of control can be used in those complex systems which have been too difficult to control or which in the past have had to rely on the experience of a human operator. Even though the significant dynamic coupling of the motors and links on the flexible joint manipulator, the performance of command-following is good by applying the proposed SOC.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.2
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• pp.141-150
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• 2004

Recently, it is really concerned about corrosion and aging of reinforced concrete bridges. Corrosional steel reinforcing in concrete affects not only safety of bridges structure but also bending strength of reinforced concrete's member. Rate of corrosion, characteristic of bending strength, and economical evaluation aren't clear in reinforced concrete, considering performance evaluation. The purpose of study is as follows. It studies about ability of resistance's strength and cost of life cycle according to reduction of steel reinforcing's corrosion. Moreover, it shows calculating formula of bending strength with corrosion of current rate and exactly evaluates about the rest life at corrosional reinforced concrete bridges.

• Journal of Korean Society of Steel Construction
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• v.20 no.1
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• pp.165-173
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• 2008

In order to promote the practicality of high-rise steel buildings, the development of structural system which have the better fire resistance, the changeable plan, and the quality control of construction with general composite beams is needed. In this research, new semi-slim floor which the defect of general slim floor was complemented was evaluated to investigate the concrete integration with slim-flor beam and the flexural performance. 5 simply supported semi-slim floor beam tests were performed with parameters; structural form of slab support beam, slab thickness, with or without web opening, and shear connection. Experimental results showed that all specimen s had good ductile behavior.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.461-462
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• 2009

Since the modal pushover analysis (MPA) is introduced by A.K.Chopra in 2002, it has been the leading procedure for the seismic evalution of structures. However it has scarcely used on bridge structures dueing to its inherent limitation. In this paper, MPA is applied on cable-stayed bridges to check its applicability on such structures.