• Research in Community and Public Health Nursing
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• v.19 no.3
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• pp.368-377
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• 2008

Purpose: The Purpose of this study was to investigate the effects of perceived stress on cognition in the community elderly. Methods: This was a descriptive study. Data were collected using individual-based interviews from 40 senior residents at the hall for the elderly in S City. The period of data collection was from June 19 to July 7, 2006. The tools of data collection were Mini-Mental State Examination (Folstein, Folstein, & McHugh, 1975) and Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1983). Results: Cognition showed significant differences according to gender education, and regular exercise. Cognition was significantly correlated to stress and age. Stress was significantly correlated to orientation, recall, and attention/calculation. In the results of stepwise multiple regression, factors affecting cognition were stress, age, and gender. Conclusion: It is necessary to prepare health promotion programs that can reduce stress level in the community elderly.

• Journal of the Korean institute of surface engineering
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• v.43 no.6
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• pp.255-259
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• 2010

In this work, Ni-Co composites incorporated with nano-sized SiC particles in the range of 45-55 nm are prepared by electroplating. The effects of plating duration on the chemical composition, surface morphology, crystalline structures and hardness have been studied. The maximum hardness of Ni-Co-SiC composite coating is approximately 633 Hv at plating duration of 1 h. The hardness is gradually decreased with increasing plating duration, which can be attributed to the growth of crystalline size and the agglomerates of SiC nano-particles. It is therefore explained that the grain refinement of Ni-Co matrix and stable dispersion of SiC particles play an important role for strengthening, which indicate Hall-Petch relation and Orowan model were dominant for hardening of Ni-Co-SiC composite coatings.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.876-883
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• 2007

The magnetic flux leakage(MFL) type nondestructive testing(NDT) method is widely used to detect corrosion, defects and mechanical deformation of the underground gas pipelines. The object pipeline is magnetically saturated by the magnetic system with permanent magnet and yokes. Hall sensors detect the leakage fields in the region of the defect. The defects are sometimes occurred in group. The accuracy of the detecting signals in this defect cluster become lowered because of the complexity of the defect cluster. In this paper, the effects of the multi -defects are analyzed. The detecting signals are computed by 3-dimensional finite element method and compared with real measurement. The results say that, rather than the size of the defects, the effects of the relative position of the multi-defects are very important on the detecting signals.

• Journal of the Korean Ceramic Society
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• v.43 no.3 s.286
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• pp.185-192
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• 2006

The effects of annealing on structural and electrical properties of ITO/PES (Indium Tin Oxide/Polyethersulfone) films was investigated. Amorphous ITO thin films were grown on plastic substrates, PES using low temperature DC magnetron sputtering. Various post annealing techniques were attempted to research variations of microstructure and electrical properties: i) conventional thermal annealing, ii) excimer laser annealing, iii) UV irradiation. The electrical properties were obtained using Hall effect measurements and DC 4-point resistance measurement. The microstructural features were characterized by FESEM, XRD, Raman spectroscopy in terms of morphology and crystallinity. Optimized UV treatment exhibits the enhanced conductivity and crystallinity, compared to those of conventional thermal annealing.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.3
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• pp.277-283
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• 2009

In this paper, aluminum doped zinc oxide (ZnO:Al) thin films on plastic substrate such as poly carbonate (PC), polyethylene terephthalate (PET) were prepared by RF magnetron sputtering method for flexible solar cell applications. Effects of the sputter pressure on the structural, electrical and optical properties were investigated. The crystallinity and the degree of the (002) orientation were deteriorated with increasing the sputter pressure. When the sputter pressure was higher, the conductivity of ZnO:Al films was improved because of the high carrier concentration and the Hall mobility. High quality ZnO:Al films with resistivity as low as $1.9{\times}10^{-3}{\Omega}-cm$ and the optical transmittance over 80 % in the visible region have been obtained on PC substrate at 2 mTorr.

• Journal of the Korean housing association
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• v.14 no.4
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• pp.131-138
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• 2003

The purpose of this study was to examine how the purchasers perceive the effects of the unit characteristics within the complex on the apartment prices. Six major characteristics of the apartments : orientations and floors; views; structures; conditions and maintenances of interior materials; interior alterations; and access to the outdoor facilities were included for the analysis. The data were gathered from 284 households in seven private apartment complexes in Ulsan. It was found that the price of the apartment was higher if it was southward, on the royal or semi-royal floors, with the nice view for the riverside or any other landscape resources, or openness. Other characteristics which increase the price were the hall type not the corridor one, inner side of the building, good conditions of interior materials, and extended balcony.

• Journal of the Korean Ceramic Society
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• v.43 no.11 s.294
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• pp.738-742
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• 2006

We report on the effects of co-doping with fluorine on properties of ZnO thin films grown by pulsed-laser deposition. The transport characteristics of Ag-F and Li-F codoped ZnO films were determined by Hall-effect measurements at room temperature. Ag-F codoped ZnO films showed n-type semiconducting behaviors. An ambiguous carrier type was observed in Li-F codoped ZnO films grown at a temperature of 500$^{\circ}C$ with the oxygen pressures of 20 and 200 mTorr. The qualities of the codoped ZnO films were studied by X-ray diffraction, atomic force microscopy, X-ray photoemission spectroscopy, and photoluminescence.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.503-510
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• 2006

Seismic control performance of MR dampers, which have severe nonlinearity, differs with respect to the dynamic characteristics of an earthquake such as magnitude, frequency and duration. In this study, the effects of excitation characteristics on the equivalent linear system of a building structure with an MR damper are investigated through numerical analysis for artificial ground motions generated from different response spectrums. The equivalent damping ratio of the structure with an MR damper is calculated using Newmark and Hall's equations for ground motion amplification factors. It is found that the equivalent damping ratio of the structure with the MR damper is dependent on the ratio of the maximum friction force of the MR damper over excitation magnitude. Frequency contents of the earthquake ground motion affects the equivalent damping ratio of long-period structures considerably. Also, additional damping effect caused by interaction between the viscousity and friction of the MR damper is observed.

• Journal of Applied and Pure Mathematics
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• v.4 no.1_2
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• pp.9-26
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• 2022

The purpose of this work is to study the existence and continuous dependence on neutral stochastic partial integrodifferential equations with impulsive effects, perturbed by a fractional Brownian motion with Hurst parameter $H{\in}({\frac{1}{2}},\;1)$. We use the theory of resolvent operators developed in Grimmer [19] to show the existence of mild solutions. Further, we establish a new impulsive-integral inequality to prove the exponential stability of mild solutions in the mean square moment. Finally, an example is presented to illustrate our obtained results.

• Journal of muscle and joint health
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• v.26 no.2
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• pp.63-71
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• 2019

Purpose: This descriptive study investigated the mediating and moderating effects of fear of fall on the relationships between health belief on fall, fall-related knowledge and fall prevention behaviors among older adults Methods: We enrolled 229 older adults residing in a senior citizen hall and community welfare center, and investigated their health belief on fall, fall-related knowledge, fall prevention behavior, and fear of fall. Descriptive statistics, ANOVA and t-test were used to analyze differences in variables. Pearson correlation and multiple regression were used to investigate mediating and moderating effects of the fear of fall on the relationships between health belief on fall, fall-related knowledge, and fall prevention behaviors. Results: The fear of fall significantly mediated the health belief on fall and fall prevention behaviors, but there was no significant mediation between knowledge of fall and fall prevention behaviors. The fear of fall did not have a moderating effect on the relationships between health belief on fall, knowledge of fall, and fall prevention behaviors. Conclusion: It is important to investigate and implement health belief on fall and fear of fall among older adults to improve their fall prevention behaviors.