• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1087-1095
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• 2009

In this paper, we study approximation method from scattered data to the derivatives of a function f by a radial basis function $\phi$. For a given function f, we define a nearly interpolating function and discuss its accuracy. In particular, we are interested in using smooth functions $\phi$ which are (conditionally) positive definite. We estimate accuracy of approximation for the Sobolev space while the classical radial basis function interpolation applies to the so-called native space. We observe that our approximant provides spectral convergence order, as the density of the given data is getting smaller.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.10 no.1
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• pp.31-37
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• 1985

An interesting area of application which makes use of the unique features of the walsh series is that on non-linear stochastic problems. In particular, some success has been obtained in improving the efficiency of signal detection for those transducers which are essentially non-linear in operation. The set of harmonically-related nonorthogonal triangle waves is shown to form a basis apanning the same function space representable by fourier(trigonometric) series. A method for generating nonorthogonal bases for signal representation is presented tailor-made basis function can be used for specific purposes. Fundamental proofs of the basis properties of the representation are examined along with examples illustrating the techniques and computer simulation.

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.2911-2916
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• 2014

The gas phase structures, energetics, and interconversion pathways of five lowest energy conformers of acetylcholine were examined employing the B3LYP, MP2, and CCSD(T) methods in conjunction with diverse basis sets including the correlation consistent aug-cc-pVDZ and aug-cc-pVTZ basis sets. It is found that use of adequate basis set containing proper polarization and diffuse functions capable of describing the floppy potential energy surface of acetylcholine is important in correctly predicting the relative stability of these conformers. The interconversion pathways and barrier heights between these conformers were elucidated by examining the potential energy surface for torsional motion, which also manifested the presence of chiral conformations of acetylcholine corresponding to the original conformations. On the basis of high level electronic energy calculations and thermal contribution analysis, four lowest energy conformers appear to be populated in the energy range of less than 1 kcal/mol at room temperature.

• The Korean Journal of Applied Statistics
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• v.27 no.4
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• pp.553-560
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• 2014

This paper deals with estimable functions of parameters of less than full rank linear model. In general, the parameters of an overspecified model are not uniquely determined by least squares solutions. It discusses how to formulate linear estimable functions as functions of parameters in the model and shows how to use projection matrices to check out whether a parameter or function of the pamameters is estimable. It also presents a method to form a basis set of estimable functions using linearly independent characteristic vectors generating the row space of the model matrix.

• Industrial Engineering and Management Systems
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• v.9 no.3
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• pp.215-226
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• 2010

Since product design strongly depends on the experience and ability of the designers, and a long lead time is required for the product design stage, introducing a support system related to this experience and ability is an effective technique to reduce the lead time. In this paper, an information system is developed to support the development of engineering mechanisms with the evaluation of the assembly process on the basis of the abstract functions required for new products. The developed system is based on a database system involving the following data structure: (1) a hierarchical structure related to information about the product functions, (2) the relationship between the parts and engineering functions and/or mechanisms of products, and (3) the relationship between the parts and manufacturing characteristics. The system stores the relationships between the product functions, structure of parts, and assembly characteristics. This information can then be interactively retrieved using the data structure described in (1), (2), and (3). A procedure for designing new products is proposed that involves using the information about existing products. This paper presents the characteristics of the proposed procedure and the developed information system. In addition, a case study of the redesign of a simple structured robot by using the proposed procedure is discussed.

• Journal of Distribution Science
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• v.19 no.3
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• pp.5-14
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• 2021

Purpose: This study aims to clarify the behavioral extraction and ability of venture merchants, who actively challenge commerce in the face of harsh living environments. Research design, data and methodology: Adopting the concept of retail functions and retail skills, this study examines how venture merchants perform retail functions, and identifies the required retail skills. This study analyzed primary data obtained through an interview with a bookstore called Lunuganga. Results: The venture merchant purchases products based on his self-assertion and creates an original "store identification." Moreover, he draws a changing "own-store customers image" and acquires "own-store customers," that is, customers acquired by him by building an original store identity. He sells products to "own-store customers" who identify with the store. The retail skills identified as required by venture merchants to carry out such retail functions were "skill to draw a store identification" and "skill to draw own-store customer image." Conclusions: Venture merchants' unique retail functions and retail skills suggest a new basis for the existence of small and medium-sized retailers. It is necessary to build a generalized theoretical hypothesis model by refining the concept presented in this paper by repeating research targeting venture merchants in the same industry and different industries.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.3
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• pp.339-345
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• 2007

In this paper, a variational formulation for plane elasticity problems is derived based on an isogeometric approach. The isogeometric analysis is an emerging methodology such that the basis functions for response analysis are generated directly from NURBS (Non-Uniform Rational B-Splines) geometry. Furthermore, the solution space for the response analysis can be represented in terms of the same functions to represent the geometry, which enables to provide a precise construction method of finite element model to exactly represent geometry using B-spline base functions in CAD geometric modeling and analyze arbitrarily shaped structures without re-meshing. In this paper, a continuum-based adjoint sensitivity analysis method using the isogeometric approach is extensively derived for the plane elasticity problems. The conventional shape optimization using the finite element method has some difficulties in the parameterization of geometry In the isogeometric analysis, however, the geometric properties are already embedded in the B-spline basis functions and control points so that it has potential capability to overcome the aforementioned difficulties. Through some numerical examples, the developed isogeometric sensitivity analysis method is verified to show excellent agreement with finite difference sensitivity.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.2
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• pp.67-78
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• 2021

This study aims to analyze how students' design work functions affect consumer attitudes and purchase intentions toward clothes designed by students, while exploring the moderating effect of price sensitivity in such a relationship. Data was acquired from 351 responses of an online questionnaire (www.sojump.com). A two-step approach was employed to analyze our hypotheses using structural equation modeling (SEM) in SPSS 22.0 and AMOS 22.0 statistical packages. First, significant empirical evidence was secured regarding the effects of design functions (assurance, fashion, camouflage, individuality, and comfort) on consumer attitudes toward clothes, which can lead to purchasing intention. Fashion, individuality, and comfort functions can enhance consumer attitude significantly, but assurance and camouflage have no significant influence. Among the functions, comfort has the greatest effect on consumer attitudes, indicating that when students market works as commodities, comfort should be highlighted in their designs. In this way, such products can draw the interest of many consumers. Second, empirical evidence showed that price sensitivity negatively moderates the association between attitude and purchase intention. Thus, design courses should be careful when setting student works' prices given consumer sensitivity. The optimization of the student works' cost structure can help minimize price sensitivity. Overall, the findings and their implications can serve as a basis for the commercial application of design curriculum works and provide feasible support for developing student design curriculum in the future.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.4
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• pp.293-299
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• 2004

This paper is about the extraction of basis function for ECG signal processing. In the first step, it is assumed that ECG signal consists of linearly mixed independent source signals. 12 channel ECG signals, which were sampled at 600sps, were used and the basis function, which can separate and detect source signals - QRS complex, P and T waves, - was found by applying the fast fixed point algorithm, which is one of learning algorithms in independent component analysis(ICA). The possibilities of significant point detection and classification of normal and abnormal ECG, using the basis function, were suggested. Finally, the proposed method showed that it could overcome the difficulty in separating specific frequency in ECG signal processing by wavelet transform. And, it was found that independent component analysis(ICA) could be applied to ECG signal processing for detection of significant points and classification of abnormal beats.

• Structural Engineering and Mechanics
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• v.25 no.5
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• pp.613-629
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• 2007

A finite element method (FEM) of B-spline wavelet on the interval (BSWI) is used in this paper to solve the static and vibration problems of thin plate. Instead of traditional polynomial interpolation, the scaling functions of two-dimensional tensor product BSWI are employed to construct the transverse displacements field. The method combines the accuracy of B-spline functions approximation and various basis functions for structural analysis. Some numerical examples are studied to demonstrate the proposed method and the numerical results presented are in good agreement with the solutions of other methods.