• International Journal of Reliability and Applications
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• 제9권2호
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• pp.141-152
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• 2008

This paper presents equations, which can be used to evaluate the failure frequency and the failure rate of a two identical component parallel redundant system in which each component can operate in its wear out period, and the failure rate of each component is exponential power distribution. The optimum maintenance interval for a two identical component parallel redundant system can be obtained using these equations. The proposed approach is presented and illustrated using several numerical examples. The optimum maintenance interval for each component in a two identical parallel redundant system will depend on factors such as: failure rate, repair and maintenance times of each component in the parallel redundant systems.

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.179-187
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• 2013

We describe newly developed software named KPACK for relativistic electronic structure computation of molecules containing heavy elements that enables the two-component ab initio calculations in Kramers restricted and unrestricted formalisms in the framework of the relativistic effective core potential (RECP). The spin-orbit coupling as relativistic effect enters into the calculation at the Hartree-Fock (HF) stage and hence, is treated in a variational manner to generate two-component molecular spinors as one-electron wavefunctions for use in the correlated methods. As correlated methods, KPACK currently provides the two-component second-order M${\o}$ller-Plesset perturbation theory (MP2), configuration interaction (CI) and complete-active-space self-consistent field (CASSCF) methods. Test calculations were performed for the ground states of group-14 elements, for which the spin-orbit coupling greatly influences the determination of term symbols. A categorization of three procedures is suggested for the two-component methods on the basis of spin-orbit coupling manifested in the HF level.

• Journal of the Korean Society of Combustion
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• 제6권2호
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• pp.1-7
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• 2001

In order to elucidate the turbulent burning velocity of the two-component fuel mixtures, the lean and rich two-component fuel mixtures, where methane, propane and hydrogen were used as fuels, were prepared keeping the laminar burning velocity nearly the same value. Clear difference in the measured turbulent burning velocity at the same turbulence intensity can be seen among the two-component fuel mixtures with different addition rate of fuel, even under nearly the same laminar burning velocity. The burning velocities of lean mixtures change almost monotonously as changing addition rate, those of rich mixtures, however, do not show such a monotony. These phenomena can be explained qualitatively from the local burning velocities, estimated by considering the preferential diffusion effect for each fuel component. In addition, a prediction expression of turbulent burning velocity proposed for the one-component fuel mixtures can be applied to the two-component fuel mixtures by using the estimated local burning velocity of each fuel mixture.

• Kyungpook Mathematical Journal
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• 제48권2호
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• pp.241-254
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• 2008

We define the crosscap number of a 2-component link as the minimum of the first Betti numbers of connected, non-orientable surfaces bounding the link. We discuss some properties of the crosscap numbers of 2-component links.

• Honam Mathematical Journal
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• 제37권1호
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• pp.99-112
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• 2015

In this paper we consider the periodic Cauchy problem for the generalized two-component Hunter-Saxton system with analytic initial data and we prove a Cauchy-Kowalevski type theorem for the generalized two-component Hunter-Saxton system, that establishes the existence and uniqueness of real analytic solutions.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.803-808
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• 2012

We have implemented two-component spin-orbit relativistic effective core potential (SOREP) methods in an all-electron relativistic program DIRAC. This extends the capacity of the two-component SOREP method to many ground and excited state calculations in a single program. As the test cases, geometries and energies of the small halogen molecules were studied. Several two-component methods are compared by using spin-orbit and scalar relativistic effective core potentials. For the $I_2$ molecule, excitation energies of low-lying excited states agree well with those from corresponding all-electron methods. Efficiencies in SOREP calculations enhanced by using symmetries are also discussed briefly.

• Journal of Microbiology and Biotechnology
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• 제24권9호
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• pp.1291-1299
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• 2014

Recently, multifunctional nanomaterials have been developed as nanotherapeutic agents for cellular imaging and targeted cancer treatment because of their ease of synthesis and low cytotoxicity. In this study, we developed a multifunctional, two-component nanorod consisting of gold (Au) and nickel (Ni) blocks that enables dual-fluorescence imaging and the targeted delivery of small interfering RNA (siRNA) to improve cancer treatment. Fluorescein isothiocyanate-labeled luteinizing hormone-releasing hormone (LHRH) peptides were attached to the surface of a Ni block via a histidine-tagged LHRH interaction to specifically bind to a breast cancer cell line, MCF-7. The Au block was modified with TAMRA-labeled thiolated siRNA in order to knock down the vascular endothelial growth factor protein to inhibit cancer growth. These two-component nanorods actively targeted and internalized into MCF-7 cells to induce apoptosis through RNA interference. This study demonstrates the feasibility of using two-component nanorods as a potential theranostic in breast cancer treatment, with capabilities in dual imaging and targeted gene delivery.

• Bulletin of the Korean Chemical Society
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• 제24권6호
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• pp.809-811
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• 2003

This brief review contains surveys of both four-component and two-component relativistic molecular theories. First the four-component relativistic approach is reviewed. Emphasis is placed on efficient computational schemes for the four-component Dirac-Hartree-Fock and Dirac-Kohn-Sham methods. Next, in the twocomponent relativistic framework, two relativistic Hamiltonians, RESC and higher-order Douglas-Kroll (DK), are introduced. An illustrative application is shown for the relativistic study on valence photoelectron spectrum of OsO₄. The developing four-component relativistic and approximate quasi-relativistic methods have been packed in a program suite named REL4D.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.213-217
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• 1999

An expert system is developed for rational and efficient design of multi-component injection molding which is a fairly new manufacturing technique to produce plastic parts by injecting two or more materials sequentially using multiple injection units in a single machine into a single rotary mold. The knowledge base used in the present design system is primarily composed of two parts ; knowledge from domain expert and knowledge from CAE analysis. The present expert system has hour main modules ; general design guidelines for injection molding specific guidelines for multi-component injection molding redesign guidelines from the result of the CAE analysis and finally troubleshooting for multi-component injection molding. To show the validity of the present design methodology two shop floor design problems were tested ; design and fabrication of timing belt cover and power window's assist knob by using multi-component injection molding.

• IE interfaces
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• 제22권2호
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• pp.165-173
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• 2009

This paper considers a two-component assembly system that makes different types of purchasing contracts by component type and studies the issue of coordinating those contracts. Acquisition of type 1 component is based on the long-term contract. In contrast, type 2 component is intermittently purchased under the sort-term contract. We identify the structural properties of the optimal short-term contract and investigate how the changes in system parameters affect the optimal performance. To provide managerial insights, we compare the short-term and long-term contracts for type 2 component and discuss the conditions that make the short-term contract preferable to the long-term contract. We also present a result which shows that coordinating the contracts of type 1 and type 2 components can be significantly profitable over uncoordinating them.