• The Journal of the Acoustical Society of Korea
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• v.32 no.5
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• pp.402-407
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• 2013

In this paper, an analysis of sound propagation between two rooms with different mediums is discussed. Statistical energy analysis (SEA) is used to consider energy equilibrium among subsystems associated with the sound pressure levels in two rooms and the vibration level of the wall between rooms. Effect of the sound radiation from the structure-borne noise of the wall on sound pressure level of the receiving room is investigated. For a numerical example, sound propagation between engine room and water tank joined by a steel plate whose size is $8.4{\times}4$ m, is considered. It is found that when the critical frequency of the plate is above the frequency range of interest, the sound pressure level in the water tank is dominated by sound transmission through the plate, while sound radiation from the structure-borne noise of the plate is negligible except low frequency range below 63 Hz.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4E
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• pp.164-169
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• 2002

This paper proposes a hybrid method for vibration analysis in the medium to high frequency ranges using Power Flow Analysis (PFA) algorithm and Statistical Energy Analysis (SEA) coupling concepts. The main part of the developed method is the application of coupling loss factor (CLF) suggested in SEA to the power transmission, reflection coefficients in PI' A boundary conditions. The developed hybrid method shows very promising results with regard to the applications for the various damping loss factors in wide frequency ranges. And also this paper presents the applied results of Power Flow Finite Element Method (PFFEM) by forming the new joint element matrix with CLF to analyze the various plate structures in shape. The analytical results of automobile, complex plate structures show good agreement with those of PFFEM using the PFA coefficients.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.164-164
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• 2002

This paper proposes a hybrid method for vibration analysis in the medium to high frequency ranges using Power Flow Analysis (PFA) algorithm and Statistical Energy Analysis (SEA) coupling concepts. The main part of the developed method is the application of coupling loss factor (CLF) suggested in SEA to the power transmission, reflection coefficients in PI' A boundary conditions. The developed hybrid method shows very promising results with regard to the applications for the various damping loss factors in wide frequency ranges. And also this paper presents the applied results of Power Flow Finite Element Method (PFFEM) by forming the new joint element matrix with CLF to analyze the various plate structures in shape. The analytical results of automobile, complex plate structures show good agreement with those of PFFEM using the PFA coefficients.

• Environmental Engineering Research
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• v.16 no.1
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• pp.19-27
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• 2011

This paper introduces an approach to identify the total energy consumption with subsequent $CO_2$ emissions, for both industrial and non-industrial sectors. Statistical data for 2005 were compiled in a national account system to construct an energy input-output table for investigating the influence between energy demand and supply activities. The methodological approach was applied to South Korea. Twelve types of energy and fifteen industrial and non-industrial sectors are formed as the compartments of the input-output table. The results provided quantitative details of the energy consumption and identified the significant contributions from each sector. An impact analysis on the $CO_2$ emissions for the demand side was also conducted for comparison with the supply side.

• International Journal of Automotive Technology
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• v.7 no.4
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• pp.423-439
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• 2006

This paper proposes a hybrid analytic method for the prediction of vibrational and acoustic responses of reverberant system in the medium-to-high frequency ranges by using the PFA(Power Flow Analysis) algorithm and SEA(Statistical Energy Analysis) coupling concepts. The main part of this method is the application of the coupling loss factor(CLF) of SEA to the boundary condition of PFA in reverberant system. The hybrid method developed shows much more promising results than the conventional SEA and equivalent results to the classical PFA for various damping loss factors in a wide range of frequencies. Additionally, this paper presents applied results of hybrid power flow finite element method(hybrid PFFEM) by formulating the new joint element matrix with CLF to analyze the vibrational responses of built-up structures. Finally, the analytic results of coupled plate structures and an automobile-shaped structure using hybrid PFFEM were predicted successively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.849-854
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• 2000

Statistical energy analysis is suitable for shipboard noise prediction in many respects. It could effectively model the large and complicated ship structures for noise analysis. This paper introduces the procedure of SEA for shipboard noise analysis gained from author's experiences in the past few years. Also, prediction accuracies of shipboard noise analysis using statistical energy analysis are discussed. It is found that the prediction results could be much improved when using the actual measured data of source levels and material properties such as loss factors, absorption coefficients and etc.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.10a
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• pp.385-390
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• 1997

In recent years there has been an increasing emphasis on shortening design cycles for bringing products to market. This requires the development of computer aided engineering tools which allow analysts to quickly evaluate the effect of design changes on noise, vibration, and harshness. Statistical Energy Analysis (SEA) modeling is a valuable tool for predicting noise and vibration as SEA models are inherently simpler and more robust than deterministic models. SEA modeling can be combined with design sensitivity analysis (DSA) to identify design changes which give the largest performance benefit. This paper describes SEA modeling of an equipment cab. SEA predictions are compared to test data, showing good agreement. The use of design sensitivity analysis in improving cab design is then demonstrated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.371.1-371
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• 2002

At lift-off, the jet noise of launch vehicle produces a severe acoustic environment and the loads induced by the acoustic pressure may be damaging to paylaod and equipments. Prediction of the acoustic environment is needed to support the design and test-qualification of components. Currently, such a high frequency problem is usually dealt with by using the SEA, of which the assumptions match reasonably well with the vibro-acoustic condition of system. (omitted)

• Communications for Statistical Applications and Methods
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• v.26 no.1
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• pp.57-67
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• 2019

Income distribution is a major concern in economic theory. In regional economics, it is often of interest to compare income distributions in different regions. Traditional methods often compare the income inequality of different regions by assuming parametric forms of the income distributions, or using summary statistics like the Gini coefficient. In this paper, we propose a nonparametric procedure to test for heterogeneity in income distributions among different regions, and a K-means clustering procedure for clustering income distributions based on energy distance. In simulation studies, it is shown that the energy distance based method has competitive results with other common methods in hypothesis testing, and the energy distance based clustering method performs well in the clustering problem. The proposed approaches are applied in analyzing data from China Health and Nutrition Survey 2011. The results indicate that there are significant differences among income distributions of the 12 provinces in the dataset. After applying a 4-means clustering algorithm, we obtained the clustering results of the income distributions in the 12 provinces.

• Nuclear Engineering and Technology
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• v.19 no.4
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• pp.249-265
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• 1987

For the probabilistic risk assessment of the high level radioactive waste repository, some methods have been proposed up to now. Since the system has highly uncertain input parameters, the evaluated risk for some input parameter values has high uncertainty. In this paper, methods of uncertainty and sensitivity analysis are devised to analyse systematically these factors and applied to a probabilistic risk assessment model of the high level waste repository, The statistical package SPUSA developed through this study can be used for any other fields, e.g., statistical thermal margin analysis, source term uncertainty analysis, etc.