• 한국정밀공학회지
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• 제16권6호
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• pp.108-113
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• 1999

For cylindrical shells, the closed-form solutions are confined to the specific boundary and/or loading conditions. Though the finite element method is certainly a powerful solution approach for the structural dynamics problems, it has been well known to provide the solution reliable only in the low frequency region due to the inherent high sensitivities of structual and numerical modeling errors. Instead, the spectral element method has been proved to provide accurate dynamic characteristics of a structure even at the ultrasonic frequency region. Since the wave characteristic of a cylindrical shell becomes identical to that fo a flat plate as the frequency increases, an equivalent plate model (EPM) representing the high-frequency dynamic characteristics of the cylindrical shell is introduced herein. The EPM-based spectral element analysis solutions are compared with the known analytical solutions for the cylindrical shells to confirm the validity of the present modeling approach.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.282-284
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• 2001

The antiallergic drug, cetirizine, inhibits the histamine release from a rat basophilic leukemia (RBL-2H3) cell line, which is frequently used as a mast cell model. By investigating inhibitory activities of (+)- and (-)-cetirizine in RBL-2H3 cells on the histamine release, we aimed to evaluate the effect of their structual characteristics on the antihistamine activity. The study on RBL-2H3 cell has clearly demonstrated that the (-)-cetirizine is significantly more potent than the (+)- or the racemic cetirizine, although there was no difference in pharmacokinetics between (+)- and (-)-cetirizine in rats.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.79-81
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• 1996

We fabricated SrTiO$_3$thin film capacitor on the Ag/Si-wafer by RF sputtering deposition. And I-V characteristics and structual analysis of the thin film capacitor are investigated. We found that the leakage current of the films during deposition is strongly denpent on the ambient gas and substrate temperature. Because of increase of activation energy, leakage current increased at high temperature and resistivity of the films was decreased. According to the increase of oxygen gas flow rate, the conductivity of thin film capacitor was increased and leakage current was decreased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 B
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• pp.383-385
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• 1997

Back-propagation is one of the efficient algorithms used to nonlinear optimizations or controls. In spite of its structual simplicity and learning ability, learning time is very long or bad case converge local minimum on complicate input patterns. In order to improve these matters varing learning rate and momentums were proposed. In this paper, to improve its performance fuzzy is adjusted in parameters, learning rate and momentums. Parameters are adjusted by errors and change of errors adaptively. In order to evaluate proposed method simulated with MATLAB on inverted pendulum.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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• pp.343-350
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• 1999

This study introduce how distributed object technology can be applied effectively to use in a integrated structural design systems environment with the rapid increasement in the use of network technology. The architecture and management models of the developed systems are described by the CORBA(Com mon Object Request Broke Architecture) distribution standard and objects in Java language. The proposed system can be used for communicating with data between remote designers, regardless of the H/W or S/W platforms they use. Introduction of distributed objects methodologies to a Integrated structural design systems provide advanced levels of integration in structural design environment.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.934-939
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• 2004

The Korea high-speed rail, based on the French design. It also implements new concept to increase the strength of bridge deck by adding an impact factor (dynamic intensity factor) in static load. In order to assure the dynamic stability, SYSTRA and Jeseph Penzien, a professor in CEC (the US) conducted a dynamic stability review on design phase. Analyzing the review results, they developed design criteria for dynamic behavior. This study deal with operating PSC box GIRDER equipped with measurement equipment or measured data of Seoul $\∼$ Taejeon, P.S.C BOX GIRDER bridge and steel comsition bridge equipped with measurement equipment based on structual knowledge about configuration of measuring sensor, response analysis of structure when train runs was performed by using measured data of PSC box girder to directly compare with design criteria. moreover, the dynamic stability with comparison of high-speed rail construction criteria was reviewed and analyzed based on historical records.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.564-571
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• 1998

The function of diaphragms at abutments and piers of prestressed concrete (PSC) box girder train bridge is to transfer forces from the superstructure onto bearings or column and to stiffen the superstructure cross-section against in-plane deformation. Due to large stress disturbance at diaphragm, the design for the diaphragm using conventional design method is relatively irrational than designs for other structual members. And, due to contribution to boundary condition of deck slab by the diaphragm, the behavior of deck slab near the diaphragm is different from behavior of the deck slab obtained from two dimensional analysis of the bridge, which is basis far the design of deck slab. In this paper, three dimensional behavior of deck slab near diaphragm of PSC box girder train bridge constructed by the precast span method are analyzed by using three dimensional finite element modeling. Then, strut-and-tie model is applied to design the diaphragm of PSC box girder train bridge. The modeling techniques in this paper can be applied effectively to examine the causes of cracks at deck slab near diaphragm and to design diaphragm rationally.

• 가족자원경영과 정책
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• 제5권1호
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• pp.141-150
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• 2001

This study applicates one of the five elaborated functional analyses of Piotr Stztompka to the housewives’study. The four general assumptions of plurality, wholeness, integration and boundary of the simple system issue the eight specific solutions; reciprocity, exploitation, consensus, conflict, dependence, autonomy, isolation and structural context of the relationships among the various elements of the system. From the eight specific assumptions of the housewives’studies, we have found that many managerial subsystem studies see the housewives’relationships to other elements in their reciprocity, concensus, dependence and isolation characteristics. If the assumptions of autonomy and structual context are used to this kind of study, we can understand the housewives’problem and potential but as an active subject of their humanlives, not as a simply passive primary manager of the family, and we can find a new concept of the development to change the housewives’quality of life.

• 대한인간공학회지
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• 제20권3호
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• pp.47-60
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• 2001

The purpose of this paper is propose an analytical method for evaluating user satisfaction of Internet website and identifying casual relationships between user satisfaction of Internet website and performance measures as like revisit intention and complaints using the structural equation model (SEM). This paper is intended to identify critical evaluation factors of user satisfaction for Internet website to determine criteria for evaluating the website. and use the criteria to develop a SEM model for quantitatively evaluation of each factors effects of user preference. The SEM model used 5 latent variables for the evaluation factors of website user satisfaction and 2 latent variables for performance evaluation. 2 portal sites were evaluated to construct the SEM model. and 74 subjects participated the website evaluation using the walk-through and face-to face survey method. Analysis results showed that the SEM model was statistically significant for all the 2 websites evaluated.

• 한국환경과학회지
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• 제5권1호
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• pp.35-41
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• 1996

For studying of coagulation and sedimentation in estuarine clay, we obtained several flow curves with various concentrations of sea water by using Coutte type rotational rheometer. The initial shear stress on high concentration of sea water was observed big, but after this, its value is decreasing with increasing shear rate. The maximum pick of shear stress is decreasing with the decreasing of concentration of sea water The trend is same totally above for viscosity. The sedimentation times with the concentration of sea water vary in $\infty$ ~ 5 minutes. The zeta potential is changed dramatically between 114 and 118 concentration of sea water. That is consistent with the sedimentation graph. From these results, the phenomena of coagulation and sedimentation can be explained with viscoelastic terms on structual formation among particles by the changes of surface potential affected from contacting sea water to dispersed particles.