• The Journal of the Acoustical Society of Korea
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• v.22 no.1E
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• pp.26-32
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• 2003

We propose new time-frequency (TF) tools for analyzing linear time-varying (LTV) systems and nonstationary random processes showing hyperbolic TF structure. Obtained through hyperbolic warping the narrowband Weyl symbol (WS) and spreading function (SF) in frequency, the new TF tools are useful for analyzing LTV systems and random processes characterized by hyperbolic time shifts. This new TF symbol, called the hyperbolic WS, satisfies the hyperbolic time-shift covariance and scale covariance properties, and is useful in wideband signal analysis. Using the new, hyperbolic time-shift covariant WS and 2-D TF kernels, we provide a formulation for the hyperbolic time-shift covariant TF symbols, which are 2-D smoothed versions of the hyperbolic WS. We also propose a new interpretation of linear signal transformations as weighted superposition of hyperbolic time shifted and scale changed versions of the signal. Application examples in signal analysis and detection demonstrate the advantages of our new results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.2
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• pp.114-126
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• 2009

In this paper, a versatile multi-criteria optimization concept for fatigue life prediction is introduced. Multi-criteria decision making in engineering design refers to obtaining a preferred optimal solution in the context of conflicting design objectives. Compromise decision support problems are used to model engineering decisions involving multiple trade-offs. These methods typically rely on a summation of weighted attributes to accomplish trade-offs among competing objectives. This paper gives an interpretation of the decision parameters as governing both the relative importance of the attributes and the degree of compensation between them. The approach utilizes a response surface model, the compromise decision support problem, which is a multi-objective formulation based on goal programming. Examples illustrate the concepts and demonstrate their applicability.

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.72-74
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• 1997

Integration and standardization of the related regulations and guidelines are necessary to evaluate a CFMS in a systematic manner. In this study, a hierachically categorized evaluation checklist was developed by collecting and structuring human factors issues listed in the various regulations, design requirements, and technical report. A PC-based database management system was developed to update and review the evaluation results. Standard interpretation examples, evaluation guidelines, and sample evaluation formats were also designed and integrated into the database system to reduce discrepancy in evaluation.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1187-1192
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• 2008

In this paper, a versatile multi-objective optimization concept for fatigue life prediction is introduced. Multi-objective decision making in engineering design refers to obtaining a preferred optimal solution in the context of conflicting design objectives. Compromise decision support problems are used to model engineering decisions involving multiple trade-offs. These methods typically rely on a summation of weighted attributes to accomplish trade-offs among competing objectives. This paper gives an interpretation of the decision parameters as governing both the relative importance of the attributes and the degree of compensation between them. The approach utilizes a response surface model, the compromise decision support problem, which is a multi-objective formulation based on goal programming. Examples illustrate the concepts and demonstrate their applicability.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.597-602
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• 2008

Most of structural analyses are concerned with the deformation and stress in a body subjected to external loads. In many fields, however, the interpretation of inverse problems is needed to determine surface tractions or internal stresses. In this study, the inverse processes by using the finite elements and the boundary elements are formulated for the evaluation of internal residual stresses from displacements measured on a remote surface. Small errors in the measured displacements often result in a substantial loss of accuracy of an inverse system. We use the Tikhonov regularization techniques to regularize the ill-conditioned system. Advantages and disadvantages are discussed through numerical examples.

• The Korean Journal of Applied Statistics
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• v.25 no.4
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• pp.613-620
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• 2012

In most cases of multidimensional scaling(MDS), the distances or dissimilarities among units are assumed to be symmetric. Thus, it is not an easy task to deal with asymmetric distances. Asymmetric MDS developed so far face difficulties in the interpretation of results. This study proposes a much simpler asymmetric MDS, that utilizes the notion of "altitude". The analogy arises in mountaineering: It is easier (more difficult) to move from the higher (lower) point to the lower (higher). The idea is formulated as a quantification problem, in which the disparity of distances is maximally related to the altitude difference. The proposed method is demonstrated in three examples, in which the altitudes are visualized by rainbow colors to ease the interpretability of users.

• Language and Information
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• v.12 no.2
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• pp.115-137
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• 2008

We examine the meanings of two plural forms in Korean. Kwak (2003) and Jun (2004) claimed that unmarked (i.e. zero) plural forms denote groups and 'deul' plural forms denote sums, and Kang (2007) indicated problems in such claims. Soon after, Jun (2007) raised an objection to Kang's view by slightly modifying his former analysis, and now this paper is a reply to Jun (2007). Jun's revision of his former view is one step forward but still it is faced with many authentic counter examples. In the mean time, Noh (2008) raised an objection to Kang (2007) from a totally different direction, claiming that unmarked forms are not plural but only singular. This position is not sound, either. We have so many cases where unmarked forms are used with plural interpretation. All in all, our view that unmarked forms denote singular as well plural individuals(sums, groups) and 'deul' forms denote only plural individuals(sums, groups) is to be maintained.

• Lingua Humanitatis
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• v.1 no.1
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• pp.295-321
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• 2001

This paper attempts to demonstrate how the linguistic and mythological features of the shamanic language make it incantatory, or ′enchanting′. Passages used in shamanic rites manifest linguistic characteristics that point to their own norms and conventions, as well as some mythological features that contribute to the undecipherablity of the shamanic language. Focusing on the estranged linguistic and mythological features, I propose that shamanic languages can be best interpreted in terms of the linguistic hierarchization, a notion that has been developed since Roman Jakobson′s poetics. The present study adopts Eisele′s framework that reinterprets Jakobsonian hierarchization into a slightly revised notion on the basis of the "degree of combinatorial freedom" and the "degree of semantic immediacy", looking into a set of paradigm examples in search of some parallel structures characterizing the shamanic language. The enchanting effect of this peculiar form of language, it is argued, is due mostly to the frequent use of lexical parallelism, which works in the reverse direction of the normal process of interpretation.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.167-172
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• 2007

The frequency-domain small-loop electromagnetic (EM) instruments are increasingly used for shallow environmental and geotechnical surveys because of their portability and speed. However, it is well known that the data quality is generally so poor that quantitative interpretation of the data is not justified in many cases. We present an inversion method that allows the correction for the calibration errors and also constructs multidimensional resistivity models. The key point in this method is that the data are collected at least at two different heights. The forward modeling used in the inversion is based on an efficient 3-D finite-difference method, and its solution was checked against 2-D finite-element solution. The synthetic and real data examples demonstrate that the joint inversion recovers reliable resistivity models from multi-frequency data severely contaminated by the calibration errors.

• Transactions of Materials Processing
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• v.9 no.6
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• pp.567-573
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• 2000

An analysis system for evaluating the design of dieface of stamping press dies is developed. The die design analysis system interfaced with CATIA via universal or NASTRAN data format provides the design information such as binder-wrap, punch contact status, section length change ratio, wrinkle symptom etc., which are crucial in predicting the defects of initial shape of the sheet in the dieface design stage. The graphic post-processor of developed system which displays 3-dimensional shapes of tool and die and analysis results, helps the interpretation of design evaluation. The dieface design analysis system was tested in draw dies of front floor panel and quarter panel of auto-body in order to verify the usefulness and validity of the system The examples show that the developed system would be a good tool in evaluating dieface designs.