• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1109-1111
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• 1997

The purpose of this paper is to analyze the effects of switching-over control for power system stabilization. Switching-over control is applied to western part of korea electric power system to improve transient stability and short-circuit capacity. It's effectiveness is demonstrated in terms of fault current level and critical clearing time which is quantitative evaluation means of transient stability. The effect of generator tripping for power system stabilization is also presented.

• Geomechanics and Engineering
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• v.1 no.2
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• pp.155-168
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• 2009

Breakdown pressures obtained from the classic, linear elastic breakdown model are compared with the corresponding pressures obtained using a nonlinear material model. Compression test results obtained on sandstone and siltstone are used for that purpose together with previously formulated nonlinear model which introduces elasticity functions to address nonlinear stress-strain behaviour of rocks exhibiting stress-dependent mechanical properties. Linear and nonlinear collapse pressures are also compared and it is shown that material nonlinearities have significant effect on both breakdown and collapse pressures and on tangential stresses which control breakdown pressure around a borehole. This means that the estimates of ${\sigma}_H$ made using linear models give stress values which are different than the real values in the earth. Thus the importance of a more accurate analysis, such as provided by the nonlinear models, is emphasised. It is shown, however, that the linear elastic model does not necessarily over-predict borehole stresses and the opposite case can be true, depending on rock type and test interpretation.

• Earthquakes and Structures
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• v.8 no.6
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• pp.1407-1433
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• 2015

The objections raised by researchers to the design provisions reported in Eurocode 8 make the efficient seismic performance of the eccentrically braced structures designed according to this code unlikely. Given the rationality and the number of the objections, this paper aims to summarize the criticism of researchers and report the opinion of the Authors. The objections raised to the design procedure of eccentrically braced structures regard aspects common to the design of steel structures and aspects specifically related to the design of eccentrically braced structures. The significance of these objections is also shown by means of exemplary cases.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.10 no.1
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• pp.42-48
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• 1984

The comparative detergency of Sodium dodecyl sulfate (SDS) solution near the first critical micelle concentration (CMC) was measured by means of a 131 I-labelled castor oil as a soil. More than 95% radiochemical purity of 131 I-labelled castor oil was obtained using potassium lidide as a carrier. Polyester test fabric was soiled with 131 I-labelled castor oil, and washed in a conventional washing apparatus mounted on appropriate devices. Fabric radioactivities were measured before and after washing by a scintilation counter. Near the first CMC, the detergency of SDS was increased with decreasing of surface tension of SDS. It was also shown that 131 I-labelled castor oil was useful for studying the detergency of SDS.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1550-1556
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• 2009

The sophisticated technologies, ensuring both stability and curving performance, are required for the medium high speed train running on conventional railway line where tangent and curved section mixed together. We can hardly meet the both requirements conflicting each other with the conventional type of bogie. Effective solution is to apply stabilizing mechanism for the bogie design, which increase hunting stability or dynamically critical speed while maintaining curving performance. In this research the numerical analysis by means of multi-body dynamic simulation S/W, experiments by using roller test rig and main line running test have been comprehensively performed for the 200km/h Korean Tilting Train with newly developed stabilizer. The paper proposes the effectiveness of stabilizer and its usefulness based on the results of analyses.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.423-430
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• 1998

Elastomeric bearings are frequently used as a means to isolate structural systems from earthquake loadings. The combination of rubber layers and reinforcing steel shims makes the bearings stiff axially but soft laterally The shear flexibility of these short columns can lead to relatively low buckling loads which may be further reduced when high shear strains are simultaneously imposed. The area reduction formula has been proposed to account for the reduction in buckling load due to shear. The result obtained from the formula is presumed to be conservative but the degree of conservatism is unknown. This paper describes a numerical study which aims at determining the effect of high shear strain on the critical load of rubber bearings. The results from the finite element analysis which accounts for both the material and geometric non-linearities are compared against the theoretical results in order to examine the validity of the theoretical formulas.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.127-132
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• 2007

This paper has the object of investigating dynamic stability of opening thick plates on Pasternak foundation by means of finite element method and providing Kinematic design data for mat of building structures. Finite element analysis of Tapered Thick plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on Pasternak foundation. the Winkler foundation parameter is varied with $10^2$, $10^3$ and the shear foundation parameter is 5, 10. The ratio of force to critical load is applied as 0.4, 0.6, respectively. This paper analyzed varying Tapered Ratio and Concentrated Mass.

• The Journal of Industrial Distribution & Business
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• v.6 no.1
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• pp.37-40
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• 2015

Purpose - Investors, creditors, governments, and others make decisions using reasonable information provided by others. In many cases, the users of this information have goals and objectives conflicting with those of the information's producers, indicating the need for external auditors. Research design, data, and methodology - Competition in auditing has noticeably intensified globally, especially in developed countries. This means that auditors are striving to increase the efficiency of their methods. In recent years, risk-based auditing has become prominent among these efforts. In risk-assessment auditing, the auditor may directly affect the effectiveness and efficiency of the audit. Results - As a central framework, the risk assessment process improves audit quality and effectiveness such that the audit will lead to necessary changes. Previous studies have shown that risk assessment affects the nature, timing, and content of audit procedures. Conclusions - In the planning stage of an audit, audit risk assessment may identify any inappropriate or inefficient distribution of resources or determine whether the results of an audit will be ineffective or incorrect. Thus, assessing audit risk is a critical task.

• Proceedings of the KSR Conference
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• 1998.05a
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• pp.211-218
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• 1998

The demand prediction becomes an essential mean to utilize efficiently finite traffic facilities and to provide the optimized schedules for transportation system. The demand prediction is one of the critical complex management schemes for distibuting resources of transportation service by means of computer system. The construction of a prediction model is based on data granulization, followed by processing the raw input data and evaluating the predicted output values. A large number of economic-social parameters are also to be implemented in conventional prediction models which are only based on a sequence of past data. The proposed prediction models are classified by static and dynamic characteristics and its performances are evaluated utilizing computer simulation.

• Journal of architectural history
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• v.6 no.2 s.12
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• pp.53-64
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• 1997

The language of architecture is a kind of tool which helps people to experience the environment not as the thing itself but as a meaningful one. It, gathered by place, constitutes 'genius loci', as the existential structures. It, in other words, gives a thing 'cognitive quality', and serve people to 'dwell' because 'a place is a gathering thing with concrete presence.' Our environment, only when it possesses the language, presents itself as a namable thing or an understood world. Such a meaningful identification is dwelling. The modern world is a complex melting-pot. It is 'complexities' and 'contradiction'. The language of architecture is never created, rather it is selected by needs of the time and the place. In this sense, architectural design means discovery and interpretation of the poetic order of architypal form and style, and the poetic order is a way for people to dwell in the humanistic sense. These reminds me of Martin Heidegger's statement : "Architecture belongs to poetry, and its purpose is to help man to dwell."