• Journal of the Korean Data and Information Science Society
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• v.28 no.4
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• pp.721-731
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• 2017

In this study, principal component analysis methods using Lasso penalty are introduced. There are two popular methods that apply Lasso penalty to principal component analysis. The first method is to find an optimal vector of linear combination as the regression coefficient vector of regressing for each principal component on the original data matrix with Lasso penalty (elastic net penalty in general). The second method is to find an optimal vector of linear combination by minimizing the residual matrix obtained from approximating the original matrix by the singular value decomposition with Lasso penalty. In this study, we have reviewed two methods of principal components using Lasso penalty in detail, and shown that these methods have an advantage especially in applying to data sets that have more variables than cases. Also, these methods are compared in an application to a real data set using R program. More specifically, these methods are applied to the crime data in Ahamad (1967), which has more variables than cases.

• Journal of Science Education
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• v.33 no.1
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• pp.31-43
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• 2009

The purpose of this study is to identify a domain-specificity of the scientific creativity and the component of scientific creativity. Conducted from theoretical study, this study suggests that a domain-specific view of creativity offers a more useful and constructive components of scientific creativity based on the literature associated with the component of scientific creativity. Scientific creativity has a domain-specific component and so there is need to distinguish scientific creativity from creativity in general. As a result, scientific creativity is different from other creativity it is concerned with scientific knowledge, science process skill, creative scientific problem finding and solving and so on. And since scientific creativity is a kind of ability, it is possible to improve through a scientific creativity program.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.357-363
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• 1986

The thermal conductivity and thermal diffusivity of food are heavity dependent on temperature and composition. The thermal properties of pure component solids were determined by the proposed model at a temperature range of $-40^{\circ}C\;to\;150^{\circ}C$ from the experimental values of 10%, 30% and 60% solid content suspensions. The major components of food products were proteins(albumin, casein, whey protein, meat protein and gluten), lipids (milk fat, vegetable oil, lard and corn oil), carbohydrates (dextrose, lactose, sugar and starch), fibers (cellulose and pectin), all milk salts. A modified probe method was used to measure these properties of pure component suspensions of each major component of food products. General mathematical models which were developed by an optimization technique can be applied to predict the properties of food products.

• Journal of Korean Neurosurgical Society
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• v.54 no.6
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• pp.518-520
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• 2013

Ossified lipoma or osteolipoma are rarely reported. It is defined as a histologic variant of lipoma that has undergone osseous metaplasia. Osteolipoma presents with a dominant osseous component within a lipoma. We report a case of a histologically confirmed osteolipoma on the nuchal ligament independent of bone. The patient was a 51-year-old female who presented with a 5-year history of a painless, progressively enlarging mass on the posterior neck. Computed tomography and magnetic resonance imaging showed a circumscribed mass compatible with fat between the C2 and C6 spinous processes with a large calcified irregular component. The mass with dual components was totally removed under general anesthesia and no recurrence was observed after 6 months of follow-up. We also reviewed the clinicopathologic features of previously reported osteolipomas in the literature and suggest that although osteolipoma is a rare variant of lipoma, it should be considered in the differential diagnosis when a lipoma of the posterior neck mixed with a bony component is encountered.

• Smart Structures and Systems
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• v.6 no.4
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• pp.349-362
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• 2010

Ultrasonic Guided Waves (UGWs) are a useful tool in structural health monitoring (SHM) applications that can benefit from built-in transduction, moderately large inspection ranges and high sensitivity to small flaws. This paper describes a SHM method based on UGWs, discrete wavelet transform (DWT), and principal component analysis (PCA) able to detect and quantify the onset and propagation of fatigue cracks in structural waveguides. The method combines the advantages of guided wave signals processed through the DWT with the outcomes of selecting defect-sensitive features to perform a multivariate diagnosis of damage. This diagnosis is based on the PCA. The framework presented in this paper is applied to the detection of fatigue cracks in a steel beam. The probing hardware consists of a PXI platform that controls the generation and measurement of the ultrasonic signals by means of piezoelectric transducers made of Lead Zirconate Titanate. Although the approach is demonstrated in a beam test, it is argued that the proposed method is general and applicable to any structure that can sustain the propagation of UGWs.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.5
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• pp.623-629
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• 2004

In this paper, a Efficient method for the mixed image separation is presented using independent component analysis and the new fast expectation-maximization(EM) algorithm. In general, the independent component analysis (ICA) is one of the widely used statistical signal processing scheme in various applications. However, it has been known that ICA does not establish good performance in source separation by itself. So, Innovation process which is one of the methods that were employed in image separation using ICA, which produces improved the mixed image separation. Unfortunately, the innovation process needs long processing time compared with ICA or EM. Thus, in order to overcome this limitation, we proposed new method which combined ICA with the New fast EM algorithm instead of using the innovation process. Proposed method improves the performance and reduces the total processing time for the Image separation. We compared our proposed method with ICA combined with innovation process. The experimental results show the effectiveness of the proposed method by applying it to image separation problems.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.4
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• pp.41-65
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• 2002

We study a multi-component production/inventory system in which individual components are made to meet various demand types. We assume that the demands arrive according to a Poisson process, but there is a fixed probability that a demand requests a particular kit of different components. Each component is produced by a flow line with several stations in which the processing times of each station follow a two-stage Coxian distribution. The production of each component is operated by an independent base-stock policy with blocking. We assume that the time needed to assemble final products follows a general distribution and the capacity of an assembling facility is sufficiently large. The objective of this study is to obtain key performance measures such as the distribution of the number of each orders for each final product and the mean time of fulfilling a customer order. The basic principle of the proposed approximation method is to decompose the original system into a set of subsystems, each subsystem being associated with a flow line. Each subsystem is analyzed in isolation using a Marie's method. An iterative procedure is then used to determine the unknown parameters of each subsystem. Numerical results show that the accuracy of the approximation method is acceptable.

• Journal of Internet Computing and Services
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• v.7 no.4
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• pp.11-22
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• 2006

Software product-lines methodology is the software development paradigm to build the target system by customizing the variable part of software assets according to requirements. To attain this, the commonalities and variabilities of the system family should be modeled explicitly at early stage. Although the researches on general software product-lines are active, the researches on component-based real-time embedded software product-lines are rather inactive. In this paper a code generation system to support the functional variabilities via feature model and generate the code for synchronization via state model is proposed to increase the productivity of the development of the real-time embedded software product-lines.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.1
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• pp.39-45
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• 2009

An Analysis of wind is essential for planning runway direction. As a general rule, the principal traffic runway at an airport should be oriented as closely as practicable in the direction of the prevailing wind. Aircraft are able to maneuver on a runway as long as the wind component at right angles to the direction of landing and taking-off, the cross wind component, is not excessive. ICAO recommends that runway be oriented so that aircraft may be landed at least 95% of the time with allowable cross wind components not exceeding specified limits based upon the airport reference field length. Based on the recommendation, the direction of the runway or runways at an airport can be determined through graphical vector analysis on wind rose. This study is to develop the wind-rose software for planning the optimum runway direction at an airport with the raw wind data based on reliable wind distribution statistics that extend over as long as a period as possible, preferably of not less than 5 years.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.2
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• pp.125-129
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• 1983

It is customary to assume that the resistance of a jull at uniform speed may be regarded as the sum of viscous and wavemaking component resistance, or C sub(i)=C sub(v)+C sub(w), where C sub(v) is regarded as a function of Reynolds Number R and C sub(w) a function of Froude Number F. Formulae have been obtained for ∂C sub(w)/∂R, ∂C sub(v)/∂F which may be relevant in seeking theoretical grounds for possible interaction between viscous and wavemaking component resistances. The values of ∂C sub(w)/∂R are small. In general they are smaller than corresponding values of ∂C sub(v)/∂R. But although these values are small it does not follow that they are entirely negligible. The Froude assumption that the rate of change of C sub(w) with R is zero must bel regarded as incorrect.