• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.227-236
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• 2002

We have performed two kinds of experimental modal analyses fur a radial tire for passenger car under free-suspension. One is the modal analysis to obtain three-dimensional modes of tire using accelerometers and the other is the one to identify cavity resonance frequency using a pressure sensor. From the first analysis, we have obtained the three-dimensional natural modes, which makes it possible to grasp the features of the modes and to classify the vibrational modes into symmetric, non-symmetric, and antisymmetric modes in a simple way by using the experimental results. From the first and the second experimental analyses we have identified the cavity resonance frequency and its three-dimensional mode shape.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.678-683
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• 2000

The one-dimensional performance model of a torque converter has been widely used to analyze and predict the performance and dynamic behavior of a torque converter. But this model doesn't include the information of the operating fluid properties. Therefore, to precisely predict dynamic performance of a torque converter, the effect of operating conditions must be considered through experimental coefficients such as friction loss coefficient and shock loss coefficient. And these coefficients cannot be achieved without experiments or internal flow analysis. In this study, the effects of varying material properties of operating fluid according to various operating temperatures are clarified with flow analysis of a torque converter. And these results are verified by comparing with those of performance experiment.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.3
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• pp.55-63
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• 1991

Transforming small ultrasonic energy into large mechanical energy is the essential feature of ultrasonic vibration in various application fields. This energy amplification can be obtained by achieving resonance condition between booster or tool horn and transducer. When it has uniform section with small sectional area, one dimensional analysis provides good estimation of the natural frequency of the horn. But, for arbitrary shape of horn, one dimensional analysis can no longer be applied. At present, designing tool horn whose natural frequency is identical to that of transducer requires serveral stages of trial and error in actual manufacturing process. In this paper, frequency analysis program is developed to easily predict the natural frequency of ultrasonic vibration cutting tool with axisymmetry and 3- dimensional shape using finite element method.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.107-118
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• 2011

This paper performs flow analysis of ultra-high speed vehicle inside the long distance tunnel. One and three dimensional hybrid mesh was used for describing moving motion and flow analysis of an vehicle inside a long distance tunnel which over 20 km. Flow analysis and aerodynamic drag measuring were performed by three dimensional mesh: around vehicle, and pressure waves of a tunnel was measured by one dimensional mesh: the other region where rare changing of flow pattern.

• The Journal of Engineering Geology
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• v.33 no.1
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• pp.151-167
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• 2023

This study compares the revised method in loose saturated sandy ground where the LNG storage tank will be installed with an evaluation method by one-dimensional effective stress analysis using the UBC3D-PLM model. Various laboratory and field tests were conducted to establish the parameters necessary for evaluation. The revised liquefaction evaluation method using the seismic response analysis result and N value from standard penetration testing evaluated the possibility of liquefaction as high, but assessment using effective stress analysis, which can consider various liquefaction resistance factors, found the site to be somewhat stable against liquefaction. One-dimensional finite element analysis using UBC3D-PLM modeling facilitated easier assessment of stability against liquefaction than the other methods and minimized the area required for reinforcement against liquefaction. In addition, it is expected that two-and three-dimensional numerical analysis considering the foundation of the LNG storage tank can identify the seismic design and behavior when liquefaction occurs.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.2
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• pp.94-101
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• 2001

Fin effectiveness and efficiency of a thermally asymmetric rectangular fin are represented as a function of non-dimensional fin length, width, fip tip surface Biot number and the ratio of fin bottom surface Biot number to top surface Biot number. For this analysis, three dimensional separation of variables method is used. One of the results shows that fin effectiveness can be increased or decreased depending on the fin length as the fin tip surface Biot number increases while fin efficiency decreases without depending on that as the fin tip surface Biot number increases.

• Journal of Ship and Ocean Technology
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• v.5 no.4
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• pp.44-50
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• 2001

Large container carriers are suffering from lack of knowledge on reliable correlation allowances between model tests and full-scale trials, especially at fully loaded condition, Careful full-scale sea trial with a full loading of containers both in holds and on decks was carried out to clarify it. Model test results were analyzed by different methods but with the same measuring data to figure out appropriated correlations factors for each analysis methods, Even if it is no doubt that model test technique is one of the most reliable tool to predict full scale powering performance, its assumptions and simplifications which have been applied on the course of data manipulation and analysis need a feedback from sea trial data for a fine tuning, so called correlation factor. It can be stated that the best correlation allowances at fully loaded condition for both 2-dimensional and 3-dimensional analysis methods are fecund through the careful sea trial results and relevant study on the large size container carriers.

• Communications for Statistical Applications and Methods
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• v.31 no.2
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• pp.191-202
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• 2024

The goal of this paper is to show how multivariate regression analysis with high-dimensional responses is facilitated by the response dimension reduction. Multivariate regression, characterized by multi-dimensional response variables, is increasingly prevalent across diverse fields such as repeated measures, longitudinal studies, and functional data analysis. One of the key challenges in analyzing such data is managing the response dimensions, which can complicate the analysis due to an exponential increase in the number of parameters. Although response dimension reduction methods are developed, there is no practically useful illustration for various types of data such as so-called large p-small n data. This paper aims to fill this gap by showcasing how response dimension reduction can enhance the analysis of high-dimensional response data, thereby providing significant assistance to statistical practitioners and contributing to advancements in multiple scientific domains.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.3
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• pp.230-237
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• 2020

In order to design a diesel engine system and predict its performance, it is necessary to analyze the gas flow of the intake and exhaust system. A gas flow analysis in three-dimensional (3D) format needs a high-resolution workstation and enormous time for analysis. Therefore, the method of characteristics (MOC) was used for a gas flow analysis with a fast calculation time and a low-resolution workstation. An experiment was conducted on a single cylinder diesel engine to measure pressure in cylinder, intake pipe and exhaust pipe. The one-dimensional (1D) gas flow was analyzed under the same conditions as the experiment. The engine speed, valve timing and compression ratio were the same conditions and the intake pressure was inputted as the experimental results. Bent pipe such as an exhaust port that cannot be realized in 1D was omitted. As results of validation, the cylinder pressure showed accuracy, but the exhaust pipe pressure exhibited inaccuracy. This is considered as an error caused by the failure to implement a bent pipe such as an exhaust port. When analyzed in 3D, calculation time required 61 hours more based on a model of this study. In the future, we intend to implement a bent pipe that cannot be realized in 1D using 3D and prepare a method to supplement reliability by using 1D-3D coupling.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.274-278
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• 2015

There are different kinds of aircrafts, such as conventional airplane, rotorcraft, fighter, and unmanned aerial vehicle. Their shape and feature are dependent upon their assigned mission. One of the fundamental analyses during the design of the aircraft is the structural analysis. The structural analysis becomes more complicated and needs more computations because of the on-going complex aircrafts' structure. In order for efficiency in the structural analysis, a simplified approach, such as equivalent beam or plate model, is preferred. However, it is not clear which analysis will be appropriate to analyze the realistic configuration, i.e., an equivalent beam or plate analysis for an aircraft wing. It is necessary to assess the boundary between the one-dimensional beam analysis and the two-dimensional plate theory for an accurate structural analysis. Thus, in this paper, the static structural analysis results obtained by EDISON solvers were compared with the three-dimesional results obtained from MSC NASTRAN. Before that, EDISON program was verified by comparing the results with those from MSC NASTRAN program and analytic solution.