• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.9-12
• /
• 2003

This paper describes a step-by-step method to minimize design iterations in a process of product design change. In the design process, two components are coupled if a change of a component can require the other components change, and design iterations are generated by the coupling. The design iteration is one of main factors that increase design effort. In this study, three matrices are used to solve the design iteration of automatic transmission lever, Requirement-Engineering matrix, Engineering-Components matrix, and DSM(Design Structure Matrix). Firstly, with the DSM, the product architecture and conceptual design process are proposed from product function analysis. Secondly, with the QFD, the Requirement-Engineering matrix and Engineering-Components matrix present the relationship among customer requirements, engineering issues, and product components. Lastly, the results of the QFD analysis are used in the DSM to solve the component interactions and to provide design

• Bulletin of the Korean Mathematical Society
• /
• v.50 no.6
• /
• pp.2027-2034
• /
• 2013

In this article, it is proved that under some conditions every bijective Jordan triple product homomorphism from generalized matrix algebras onto rings is additive. As a corollary, we obtain that every bijective Jordan triple product homomorphism from $M_n(\mathcal{A})$ ($\mathcal{A}$ is not necessarily a prime algebra) onto an arbitrary ring $\mathcal{R}^{\prime}$ is additive.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.36 no.2
• /
• pp.74-80
• /
• 2013

In this study, a novel and flexible recommender system was developed, based on product taxonomy and usage patterns of users. The proposed system consists of the following four steps : (i) estimation of the product-preference matrix, (ii) construction of the product-preference matrix, (iii) estimation of the popularity and similarity levels for sought-after products, and (iv) recommendation of a products for the user. The product-preference matrix for each user is estimated through a linear combination of clicks, basket placements, and purchase statuses. Then the preference matrix of a particular genre is constructed by computing the ratios of the number of clicks, basket placements, and purchases of a product with respect to the total. The popularity and similarity levels of a user's clicked product are estimated with an entropy index. Based on this information, collaborative and content-based filtering is used to recommend a product to the user. To assess the effectiveness of the proposed approach, an empirical study was conducted by constructing an experimental e-commerce site. Our results clearly showed that the proposed hybrid method is superior to conventional methods.

• Journal of applied mathematics & informatics
• /
• v.27 no.3_4
• /
• pp.673-683
• /
• 2009

We point out: to make Hermtian matrices A and B satisfy Styan matrix inequality, the condition "positive definite property" demanded in the present literatures is not necessary. Furthermore, on the premise of abandoning positive definite property, we derive Styan matrix inequality of Hadamard product for inverse Hermitian matrices and the sufficient and necessary conditions that the equation holds in our paper.

• Journal of applied mathematics & informatics
• /
• v.25 no.1_2
• /
• pp.169-181
• /
• 2007

Applying the properties of Hadamard core for totally nonnegative matrices, we give new lower bounds of the determinant for Hadamard product about matrices in Hadamard core and totally nonnegative matrices, the results improve Oppenheim inequality for tridiagonal oscillating matrices obtained by T. L. Markham.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.5
• /
• pp.651-655
• /
• 2018

In this paper, based on an augmented Lyapunov-Krasovskii functional(LKF) with time-delay product quadratic terms, the stability result in the form of linear matrix inequality(LMI) is proposed. In getting an LMI result, the free matrix based integral inequality is used. Finally, two well-known numerical examples are given to demonstrate the usefulness of the proposed result.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1997.10a
• /
• pp.121-124
• /
• 1997

This paper is concerned with the generation and use of modular BOM, which is typically utilized in representing product configurations for two-level master production schedule. A method called VCM (Value Clustering Method) is proposed to build modular BOMS. We adopted a where-used matrix to represent part-product relationships. VCM is a method that can identify modules of components based on the where-used matrix. The method uses product family group value, product value, and component value. This can facilitate retrieving information about modules, finding out alternative usage pattern of components, and recognizing modules used in a particular product.

• Journal of applied mathematics & informatics
• /
• v.20 no.1_2
• /
• pp.421-431
• /
• 2006

In this paper, we establish a matrix inequality and its equivalent form. Applying the results, some matrix inequalities involving Khatri-Rao products of positive semi-definite matrices are generalized.

• Journal of Institute of Control, Robotics and Systems
• /
• v.13 no.3
• /
• pp.256-262
• /
• 2007

In mass customization, the focus is variety and customization through flexibility and quick responsiveness. Mass customizers seek to provide personalized, custom-designed products at low prices to give customers exactly what they want and to provide sufficient variety in products and services. The idea of the product family is the most adequate approach to realize mass customization. An understanding of customer needs using functional decomposition becomes necessary to enhance the performance of the product family. This paper focuses on functional architecture modeling based on customer need regarding sub-functions for the product family. A quantitative functional model captures product functionality and customer need. Based on customer need ratings and sub-function, a product-function matrix was created. Additionally, a product-product matrix was generated to provide a similarity index among product families. A case study for implementing the functional architecture modeling was performed on the single use cameras.

• Journal of applied mathematics & informatics
• /
• v.10 no.1_2
• /
• pp.101-109
• /
• 2002

We extend two inequalities involving Hadamard Products of Positive definite Hermitian matrices to positive semi-definite Hermitian matrices. Simultaneously, we also show the sufficient conditions for equalities to hold. Moreover, some other matrix inequalities are also obtained. Our results and methods we different from those which are obtained by S. Liu in [J. Math. Anal. Appl. 243:458-463(2000)] and B.-Y Wang et al in [Lin. Alg. Appl. 302-303: 163-172(1999)] .