• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.401-418
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• 2005

In this paper, a dual algorithm, based on a smoothing function of Bertsekas (1982), is established for solving unconstrained minimax problems. It is proven that a sequence of points, generated by solving a sequence of unconstrained minimizers of the smoothing function with changing parameter t, converges with Q-superlinear rate to a Kuhn-Thcker point locally under some mild conditions. The relationship between the condition number of the Hessian matrix of the smoothing function and the parameter is studied, which also validates the convergence theory. Finally the numerical results are reported to show the effectiveness of this algorithm.

• Bulletin of the Korean Mathematical Society
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• v.39 no.4
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• pp.561-569
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• 2002

In this paper we prove the existence and uniqueness of a mild solution of a functional differential equation of Sobolev type with nonlocal condition using the semigroup theory and the Banach fixed point principle.

• Journal of applied mathematics & informatics
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• v.28 no.3_4
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• pp.739-751
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• 2010

This article presents the result on existence, uniqueness and stability of mild solution of impulsive stochastic partial neutral functional differential equations under sufficient condition. The results are obtained by using the method of successive approximation.

• Journal of Sasang Constitutional Medicine
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• v.24 no.4
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• pp.28-39
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• 2012

Objectives : This study is aimed to develop the algorithm to diagnose Taeeumin's symptomology, by the method of literature research on Sasang Constitutional Medicine. Methods : Applying the sequential differentiations of Taeeumin's symptomology, or exterior-interior disease differentiation, favorable-unfavorable pattern differentiation, and mild-severe-dangerous-urgent pattern differentiation, "Donguisusebowon" and related literatures have been reviewed. Results and Conclusions : 1) 1st step: Taeeumin's exterior pattern and interior pattern are differentiated by the indexes of whole-body cold or heat pattern, sweating, and facial complexion. 2) 2nd step: The favorable pattern of the Taeeumin's exterior disease can be detected by indexes of the existence of fever, generalized pain while the unfavorable one by indexes of the abnormal condition of digestion and feces, and fearful throbbing. The favorable pattern of the Taeeumin's interior disease can be diagnosed based on indexes of eye pain, dry nose, dry throat, and heat symptoms that occur in various parts of the body, while the unfavorable one by indexes of thirsty, urination, feces and specific symptoms which can be induced by dryness. And in the both unfavorable patterns the dark complexion on the faces is revealed. 3) 3rd step: The mild-severe patterns of the favorably exterior disease are differentiated in terms of the condition of fever, while the mild-severe patterns of the favorably interior disease are in differentiated based on whether abnormal symptoms are revealed in the gastrointestinal tract. Both of the unfavorably dangerous-urgent patterns in exterior and interior diseases are differentiated by the symptoms such as tinnitus, dim vision, weakness of legs and back pain, and lack of strength in legs and thighs.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.4 s.148
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• pp.467-475
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• 2006

Fatigue strength of hull structural steel plate, extracted from longitudinal bulkhead of a 17-year-old ore/oil carrier for renewal, was investigated in air and in artificial seawater condition. The surface of the plate was covered with corrosion pits and they proved to be crack initiation sites by fractography using SEM. From this research, it was found that the evaluation method for fatigue strength of virgin mild steel plates in air and in artificial seawater can also be applied to the evaluation of the fatigue strength of mild steel plates those were long-term exposed to a corrosive environment and their surfaces had been rusted intensively.

• Journal of Fashion Business
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• v.8 no.1
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• pp.61-75
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• 2004

This paper has the meaning to plan new design of patient's cloth focusing on its aesthetic aspect through surveying actual condition of use of patient's cloth and reflecting color or pattern that patient prefers to it. Substantial purpose of this paper is 1) to survey actual condition of patient's cloth on the basis of general hospital of downtown of Busan City, 2) to revise difficulty of patient's cloth and survey and analyze color and pattern that patient prefers and 3) to suggest new patient's cloth design using color and pattern that meets function that is not difficult for patient's activity and cure and stabilizes patient's mind on the basis of the result of analysis. The result of this paper is like follow. 1. Problem of current patient's cloth is that most hospital uses patient's cloth having white background and hospital logo of blue or green color and its length is too long so it requires adjustment of length of sleeves and pants 2. The result from analyzing preferred patient's cloth is that patient prefers patient's cloth classified by man and woman, one that its length of sleeves and pants are adjusted and one that there is no collar in its neckline. Regarding color, male patient prefers mild indigo color(5PB7/7) and mild green color (5G9/2) and female patient prefers bright purple color and bright scarlet color(5YR8/7). Regarding pattern, both of man and woman prefers natural pattern. 3. This paper planned total 6 kinds of patient's cloth (common patient's cloth: 2 kinds, male patient's cloth: 2 kinds and female patient's cloth: 2 kinds) through revising difficulty and using new color and pattern according to result of preference.

• Journal of the Korean Ceramic Society
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• v.31 no.2
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• pp.177-184
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• 1994

AlN-BN ceramics with BN contents in the range of 10 to 40 wt% were prepared by hot pressing using no additive, or 3 wt%, Y2O3 or CaO, which are common densification aids for AlN. And their machinability, bend strength, and microstructures were investigated. Both the main and radial cutting forces decreased with increasing BN content in all three kinds of samples. For the BN contents of 30 wt% or above, the cutting forces were lower than that of a mild steel tested at a same condition. Especially in the case of main forces, the values were less than a quarter of that of a mild steel, indicating excellent machinability. Bend strength (when the tensile surfaces of specimens were perpendicular to the hot pressing direction) also decreased with BN content mainly due to the much lower Young's modulus of BN compared to AlN. With the composition of 30 wt% BN at which the AlN-BN ceramics started to show better machinability than a mild steel, the bend strength was 150 to 160 MPa, which is greater than that of machinable glass-ceramics of a mica system. With tensile surfaces parallel to the hot pressing direction, however, the bend strength obtained for the samples processed with the sintering acids showed low values (about 40 MPa), since most BN particles had such orientation that their cleavage planes (i.e., basal planes) were perpendicular to the pressing direction.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.4
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• pp.174-186
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• 1998

A Galerkin's finite element model incorporating infinite elements for modeling of radiation condition at infinity has been developed, which is based on an extended mild-slope equation. To illustrate the validity and applicability of the present model, the example analyses were carried out for a resonance problem in the rectangular harbor of Ippen and Goda (1963) and for wave transformations over circular shoals of Sharp (1968) and Chandrasekera and Cheung (1997). Comparisons with the results obtained by hydraulic experiments and hybrid element method showed that the present model gives very good results in spite of the rapidly varying topography. Numerical experiments were also performed for wave transformations over a circular concave well which may be an alternative to conventional wave barriers.

• Journal of Power System Engineering
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• v.1 no.1
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• pp.70-79
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• 1997

Ni-base self-fluxing alloy powder particles were flame sprayed onto the SS400 mild steel substrate surface. The effects of both substrate temperature and spraying distance on the splat behavior of sprayed particles were examined. The results obtained are summarized as follows: 1) In the splat behavior of Ni-base self-fulxing alloy particles sprayed onto the SS400 mild steel substrate, splashing was observed under the room temperature condition. On the contrary, it showed circular plate pattern in the substrate temperature range over 373K. 2) It was cleared that there was close relationship between mechanical properties of coating layer and splat behavior of sprayed particles. 3) From the experimental results, optimum spraying conditions showed excellent mechanical properties in the case of Ni-base self fluxing alloy sprayed onto the SS400 mild substrate were 473K of substrate temperature and 250mm of spraying distance.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.226-239
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• 2018

In this paper, design and control method ZVT Interleaved Bidirectional LDC(IB-LDC) for mild-hybrid electric vehicle is proposed. The IB-LDC is composed of interleaved buck and boost converters employing an auxiliary inductor and auxiliary capacitors to achieve zero-voltage-transition. Operating principle of IB-LDC according to operation mode is introduced and mathematically analyzed in buck and boost mode. Moreover, PFM and phase control are proposed to reduce circulating current for low power range. Passive components design such as main inductor, auxiliary inductor and capacitors is suggested, considering ZVT condition and maximizing efficiency. Furthermore, a 600W prototype of ZVT IB-LDC for MHEVs is built and tested to verify validity.