• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.784-798
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• 2020

This paper presents the results of research on transverse shrinkage of welded butt joints conducted according to the principles of experimental design and under production conditions for two main welding techniques used in shipbuilding (FCAW and SAW). Analysis took into account the technological and structural parameters influencing the assembly suitability of a large steel structure. The presented method of evaluation makes it possible to apply approximation formulae to predict transverse shrinkage in real sections of a ship hull. The determined predictive formulae were verified to actual transverse shrinkage measurements during prefabrication of hull sections at a shipyard as well as the equations referring to the analyzed form of deformation available in the literature.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.09a
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• pp.320-328
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• 2001

Base Isolation system is an effective design strategy that provides a practical substitute for the seismic design of bridge. In this study, the dynamic tests were performed on two kinds of aseismic bridge bearings : Hydampot (hysteretic damping bearing) and Dynapot . Then, the dynamic analysis was carried out far a bridge using the experimental results to estimate the seismic performance of the bearings. Analysis was performed for four types oi earthquake loadings. The results of the dynamic test and theoretical analysis indicate that the performance of both bridge bearings is appropriate fur the earthquake loading.

• Journal of the Korea Furniture Society
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• v.19 no.5
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• pp.375-386
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• 2008

The purpose of this study is to analysis the influence in furniture and interior design of pop design. Pop design is a trend which was in fashion for a short time between 1950s and 1960s. It is an experimental transient form in a flow of postmodernism. Through such a trend, we can analogize an idea and values of people speaking for a rapid change of society and culture chat that time. Therefore, the purpose of the study is to examine what environment of society and culture and what idea had an effect on people at that time. Also, the study will examine how the above had an effect on interior design and furniture design. Considering the above results, the study will examine an influence and meaning of pop design in design history. According to the result of analysis, characteristic of pop design is anti-modern, expendability, future mood.

• Structural Engineering and Mechanics
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• v.56 no.1
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• pp.27-47
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• 2015

In this study, the accuracy and reliability of fully nonlinear method against equivalent linear method for dynamic analysis of soil-structure interaction is investigated comparing the predicted results of both numerical procedures with the results of experimental shaking table tests. An enhanced numerical soil-structure model has been developed which treats the behaviour of the soil and the structure with equal rigour. The soil-structural model comprises a 15 storey structural model resting on a soft soil inside a laminar soil container. The structural model was analysed under three different conditions: (i) fixed base model performing conventional time history dynamic analysis, (ii) flexible base model (considering full soil-structure interaction) conducting equivalent linear dynamic analysis, and (iii) flexible base model performing fully nonlinear dynamic analysis. The results of the above mentioned three cases in terms of lateral storey deflections and inter-storey drifts are determined and compared with the experimental results of shaking table tests. Comparing the experimental results with the numerical analysis predictions, it is noted that equivalent linear method of dynamic analysis underestimates the inelastic seismic response of mid-rise moment resisting building frames resting on soft soils in comparison to the fully nonlinear dynamic analysis method. Thus, inelastic design procedure, using equivalent linear method, cannot adequately guarantee the structural safety for mid-rise building frames resting on soft soils. However, results obtained from the fully nonlinear method of analysis fit the experimental results reasonably well. Therefore, this method is recommended to be used by practicing engineers.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.11 s.170
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• pp.1871-1877
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• 1999

An optimal design method using a response surface method for dynamic characteristics of a washer is presented. The proposed method uses the design of experiment and a computer model is used for the experiment. The value of the cost function is estimated using a computer model for each case of the design variable variation. An orthogonal array is used to obtain best cases to be considered with minimum number of experimentation. Using these experimental values, optimal design is performed using a response surface method. The method used in this paper can be applied to any complicated mechanical systems that can be modelled and analyzed by a computer program. The method is applied to the design of dynamic characteristics of a washer.

• Structural Engineering and Mechanics
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• v.43 no.4
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• pp.545-560
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• 2012

Design codes provide the minimum requirements for the design of code-compliant structures to ensure the safety of the life and property. As for code-exceeding buildings, the requirements for design are not sufficient and the approval of such structures is vague. In mainland China in recent years, a large number of code-exceeding tall buildings, whether their heights exceed the limit for the respective structure type or the extent of irregularity is violated, have been constructed. Performance-based seismic design (PBSD) approach has been highly recommended and become necessary to demonstrate the performance of code-exceeding tall buildings at least equivalent to code intent of safety. This paper proposes the general methodologies of performance-based seismic analysis and design of code-exceeding tall buildings in Mainland China. The PBSD approach proposed here includes selection of performance objectives, determination of design philosophy, establishment of design criteria for structural components and systems consistent with the desirable and transparent performance objectives, and seismic performance analysis and evaluation through extensive numerical analysis or further experimental study if necessary. The seismic analysis and design of 101-story Shanghai World Financial Center Tower is introduced as a typical engineering example where the PBSD approach is followed. The example demonstrates that the PBSD approach is an appropriate way to control efficiently the seismic damage on the structure and ensure the predictable and safe performance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.514-518
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• 2000

Micro wave seeker consists of a gimbal structure, a antenna and many RF parts. And Missile's propelling powers excite a gimbal structure, a antenna and many RF parts. Therefore, We must inquire into external forces to act on a micro wave seeker before everything. We must inquire into design parameters and then estimate dynamic characteristics of a gimbal structure with a finite element model to reflect part's characteristics for design for a gimbal structure in consideration of vibration features. In this paper, a gimbal structure of a micro wave seeker is modeled in finite element method and then updated by using the experimental modal data. Before we make a finite element model of a gimbal structure of a micro wave seeker, we make a finite element model of a sub-structure and compare with the experimental modal data.

• Journal of the military operations research society of Korea
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• v.13 no.1
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• pp.45-64
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• 1987

Power algorithms for analysis of variance tests are presented. In experimental design of operational tests and evaluations the selection of design parameters so as to attain an experiment with desired power is a difficult and important problem. An interactive computer program is presented which uses the power algorithms for ANOVA tests and creates graphical presentations which can be used to assist decision makers in statistical design. ANOVA tests and associated parameters (such as sample size, types and levels of treatments, and alpha-level)are examined.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.2
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• pp.144-155
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• 1992

A design of a highly stable current-controlled power supply combining the phase-controlled rectifier (PCR), passive filter and active filter is investigated. A digital phase-looked voltage control (PLVC) with a capability of compensating the thyristor firing angles under unvalanced power source is proposed` otherwise the PCR output voltage has low-order subharmonics whose suppression requires a bulky passive filter. The digital PLVC has a fast dynamic characteristics as an inner control loop of the PCR. To suppress further the output ripple, an active filter using a transformer is introduced and its design is described through the frequency domain analysis. An optimal integral, proportional and measurable variable feedback (IPM) controller is designed using the time-weighted performance index based on the time domain analysis. The design method based on the time-weighted performance index gives better response characteristics than that based on the conventional performance index. It is also shown via experimental results that the proposed scheme gives better response characteristics than that based on the conventional performance index. It is also shown via experimental results that the proposed scheme gives good dynamic and static performances.

• International Journal of Aeronautical and Space Sciences
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• v.1 no.2
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• pp.22-29
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• 2000

A method to simulate the gas turbine transient behavior is developed. The basic principles of the method and main input data required are described. Calculation results are presented in terms of whole operating regime of the engine. The influence of initial parameters such as starting engine power, moment of inertia of the rotor, fuel schedule on performance characteristics of gas turbine during transient operation is shown. In addition, the effect of bleeding air on transient behavior is also considered. For validation of the developed computer code, a comparative analysis with experimental data obtained from a heavy duty gas turbine is made. Calculation results agree well with the experimental data for the range of operating regime studied and proved applicability of the developed technique to initial design stage of control system.