• Tribology and Lubricants
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• v.16 no.1
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• pp.39-45
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• 2000

In this paper, the effects of shaft and bearing flexibilities are investigated for the accurate modeling of a shaft-bearing system supported by ball bearings. Generally, rolling bearings are modeled by simple rigid pin-joint in the mechanical design. However, they can no longer be modeled by ideal boundary conditions in the advanced applications because the rigid pin-joint model cannot satisfy the current trends of mechanical design decreasing mass and reducing volume. Consequently the flexible support model of ball bearing is investigated using the static analysis module developed by A .B. Jones and T. A. Harris. A simple two-bearing system, supported by two deep groove ball bearings and radially loaded on the shaft midway between the bearings, is utilized to validate the coupled model of shaft-bearing system. Numerical computations using the model indicate that the shaft span length, locating/floating bearing arrangements and applied bearing size are significant factors in determining the mechanical behaviors. The flexible support model of ball bearing can be escaped to over-estimate in the bearing fatigue life. The proposed simple design formulation obtained by numerical simulations can approximately predict a rate of bearing life reduction as a function of shaft span length/shaft diameter (L/d).

• Journal of Information Management
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• v.36 no.4
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• pp.175-198
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• 2005

Information services adopting RSS(Really Simple Syndication) is on an increase. It is replacing the existing email services. Information in the area of science and technology is of vast amount and various area and their life-cycle and service is complex. Institutions providing information of a single area are not faced with many obstacles in designing information services using RSS in acquiring a channel for the service. However, RSS service in the area of science and technology has to be more specific in designing and implementing the services. In this study, RSS is compared with other information service protocols, domestic and international trends in the area of RSS is analyzed to implement the RSS based Science and Technology information service system(STI-RSS) and its service.

• The KIPS Transactions:PartD
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• v.9D no.2
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• pp.243-250
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• 2002

In order to properly interpret and process or operators in deductive databases including indefinite clauses, we propose to use Lasez′s Strong Model Semantics(LSMS) which is reasonably simple yet powerful enough to support both exclusive and inclusive interpretations. Conventional semantics either fail to support both interpretations or simply too complex. Therefore, in this paper we study advantages and difficulties of representing indefinite information, and as for the solution to difficulties, we show how LSMS can be used to support both inclusive or and exclusive or interpretations. We also investigate and analyze it′s properties and show how it semantically differs from others. We believe that LSMS is the only "reasonably simple" semantics that supports both inclusive and exclusive interpretations.

• Communications for Statistical Applications and Methods
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• v.29 no.2
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• pp.193-202
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• 2022

Semi-supervised learning has gained significant attention in recent applications. In this article, we provide a selective overview of popular semi-supervised methods and then propose a simple but effective algorithm for semi-supervised classification using support vector machines (SVM), one of the most popular binary classifiers in a machine learning community. The idea is simple as follows. First, we apply the dimension reduction to the unlabeled observations and cluster them to assign labels on the reduced space. SVM is then employed to the combined set of labeled and unlabeled observations to construct a classification rule. The use of SVM enables us to extend it to the nonlinear counterpart via kernel trick. Our numerical experiments under various scenarios demonstrate that the proposed method is promising in semi-supervised classification.

• Journal of East-West Nursing Research
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• v.14 no.2
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• pp.39-46
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• 2008

Purpose: The study was undertaken from June 1 to July 15, 2008 to assess the effect of social support on self-esteem and life satisfaction in elderly volunteers. Methods: Social support, self-esteem, and life satisfaction were determined using previously established and accepted methods. Data analyses included frequency, ANOVA, t-test, Pearson correlation coefficient, and simple regression. Results: Subjects' social support, self-esteem, and life satisfaction were closely related. The relationships of social support/self-esteem, social support/life satisfaction, and self-esteem/life satisfaction were significant. Social support accounted for 15% of self-esteem and 12% of life satisfaction. Conclusions: Social support is a very important factor influencing self-esteem and life satisfaction of the elderly. Social support, which sustains the mental health of the elderly, represents one of the best strategic nursing interventions.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.46-53
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• 1995

The anatomy of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens was described and analyzed. Sixteen wood anatomical characters, habit and phenology factors were determined by simple correlation and principal component analysis. Strong positive correlations were found between vessel element length and fiber length, ray width and ray height, simple pits of fiber wall and paratracheal parenchyma distribution. The results of principal component analysis (PCA) disclose the primitive characteristics and the direction of xylem evolution of Korean diffuse-porous woods. The xylem evolution scenario for Korean dicotyledonous woods is considered to be developed in the direction of decreasing trends of vessel frequency, vessel element length, and length/diameter(L/D) ratio of vessel element but increasing trends of vessel diameter, fiber length/vessel element length(F/V) ratio, libriform wood fibers, simple perforation, and homogeneous ray composition. Increase of vessel diameter and decrease of vessel frequency seem to be related to the improvement of conductive efficiency, and increase of the vessel element length and occurrence of scalariform perforation in vessel element may be related to enhanced of conductive safety. Also the libriform wood fibers and ray features appear to have relationship with mechanical support and nutrient metabolism, respectively.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.60-65
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• 2005

Research on RSS(Really Simple Syndication) based application and services are being deployed both domestically and internationally. The RSS service in the area of science and technology should be flexible to the various sources of information as well as the various platform and environments that they are being serviced. It also requires a standardized system to meet the above needs. We have analyzed the use of RSS services overseas as well as domestic services to suggest the implementation of standard system for the syndication of science and technology information based on RSS.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.12
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• pp.9-16
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• 2011

Most of the current mobility management protocols such as MIPv4/6 and its variants standardized by the IETF do not support global seamless handover. This is because they require comprehensive changes of the existing network infrastructure. In this article, we propose a simple mobility management protocol (SMMP) which can support global seamless handover between homogeneous or heterogeneous wireless networks. The idea is that the SMMP employs separate location management function as done in SIP to support global user and service mobility. In addition, the bidirectional tunnels are dynamically constructed to support seamless IP mobility by extending the IEEE 802.21 MIH standards. The detailed architecture and functions of the SMMP have been designed. Finally, the simulation results, using NS-2, show that the proposed SMMP outperforms the existing MIPv6 and HMIPv6 in terms of handover latency, packet loss, pear signal noise ratio (PSNR).

• Journal of the Korean Home Economics Association
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• v.40 no.5
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• pp.109-118
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• 2002

This study focused on the relationship among perceived social support from care teacher(institution staff), internal locus of control, and school adjustment of institutionalized children. This also examined the differences of perceived social support, internal thou of control, and school adjustment by gender and the duration in the institution. Participant were 119 fifth-and sixth-grade elementary school studens(58 boys, 61 girts). Perceived social support from care teacher, internal locus of control, and school adjustment were measured by self-reports of institutionalized children. The data were analyzed, in SPSS Win program, by Cronbach's α, T-test, Pearson Correlations, Simple Regression, Hierarchical Multiple Regression. As expected, results confirm that perceived social support was associated positively with internal locus of control and school adjustment. further, perceived social support also exerts indirect effects on school adjustment, mediated by internal locus of control. However, none of these variables differed by gender and the duration in the institution.

• Journal of KSNVE
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• v.10 no.1
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• pp.153-159
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• 2000

This paper presents a new method for including the dynamic stiffness of the stationary parts in rotordynamic analysis. As a consequence of the support dynamics, critical speeds are varied and/or additional critical speeds are introduced. Therefore, dynamic effects of the support are often significant in high speed turbomachinery, but most of analysis has considered the support as a rigid body or a simple structure. The proposed method is based on the coupled characteristics of the driving point and transfer frequency response functions of the support system to model the equivalent spring-mass series in finite element analysis. To demonstrate the applicability of the simulation procedures provided, it is applied to the rotor model of the double suction centrifugal pump. Results of the suggested equivalent-support rotor model including coupled effects agree well with the entire pump model.