• Journal of Korea Society of Industrial Information Systems
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• v.7 no.1
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• pp.10-15
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• 2002

It is presented to extended to an interaction matrix formulation to the problem of system and disturbance identification for a plant that is corrupted by both process and output disturbances. With only an assumed upper bound on the order of the system and an assumed upper bound on the number of disturbance frequencies, it is shown that both the disturbance-free model and disturbance effect can be recovered exactly from disturbance-corrupted input-output data without direct measurement of the periodic disturbances. The rich information returned by the identification can be used by an iterative learning or repetitive control system to eliminate unwanted periodic disturbances. Those can be helped to apply to the multiple dynamic systems for precision quality assurance.

• Communications for Statistical Applications and Methods
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• v.2 no.2
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• pp.129-134
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• 1995

The ordinary least square estimator of the disturbance variance in the pooled cross-sectional and time series regression model is shown to be asymptotically unbiased without any restrictions on the regressor matrix when the disturbances follow an equicorrelated error component models.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.363-365
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• 2002

The characteristic responds of load respect to various disturbances which can usually be occurred on actual power system is very important to analyze performance and to improve load with high-technology. The disturbance power supply is designed to provide wide range of power to testing load. This device uses PLC technology to dynamic characteristic experiment and CVVF to change frequency. Also this instrument includes data acquisition system to obtain reliable data from experiment.

• Communications for Statistical Applications and Methods
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• v.17 no.3
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• pp.349-356
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• 2010

The ordinary least squares based estimator of the disturbance variance in a regression model for spatial panel data is shown to be asymptotically unbiased and weakly consistent in the context of SAR(1), SMA(1) and SARMA(1,1)-disturbances when there is measurement error in the regressor matrix.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.242-245
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• 2005

The rotating flow in the space between co-rotating disks is of considerable importance in information storage systems. Hard disk drivers(HDD) in computer are used extensively as data storage capacity. The trend in the computer industry to produce smaller disk drives rotating at higher speed requires an improved understanding of fluid motion in the space between disks. In this study, we have tried LES model for inner-disk flowfield to investigate the flow disturbance and the flow structure driven by co-rotating disks. The boundary pattern between inner region and outer region obtained lobe-shape structure clearly and its number has been validated on experimental data by our previous study. We obtain the spectra of velocity and pressure components with several frequencies. We revealed there are two kinds of disturbances, one is global wave propagation and another is local wave propagation on Ekman boundary layer.

• Journal of Korean Clinical Health Science
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• v.2 no.3
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• pp.176-187
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• 2014

Purpose. The purpose of this study was to identify the factors affecting quality of sleep and sleep disturbance among inpatient. Methods. A descriptive correlational study was conducted Participants were 200 inpatient in a hospital located in B city. A structured questionnaire was used for data collection. Collected data were analyzed using descriptive statistics, t-test, one-way ANOVA, Pearson's correlation, and stepwise multiple regression. Result. Hospitalized patient's score of sleeping quality was 38.26 on an overall scale of 60, indicating it to be higher than 'Medium (30 points). Almost hospitalized patient in this study suffer from sleep disturbances. As results of univariate analyses, Educational level, Departments, Why hospitalized, Insomnia / depression, Chronic Disease, Scale of pain, physical symptoms, environmental factors, emotional factors, and sleep promoting behavior, disturbed sleep among hospitalized. However, the result of stepwise multiple regression analysis identified that physical symptoms, environmental factors, emotional factors, sleep promoting behavior, and Why hospitalized disturbed sleep and were significant score of sleeping quality for hospitalized and these sleep disturbance factors accounted 46.8% of variance of sleeping quality among hospitalized. Conclusion. These findings suggest that hospitalized patients with poor sleep quality should have their health carefully screened for physical symptoms, environmental factors, emotional factors, sleep promoting behavior, and why hospitalized. In addition, we recommend the development of a nursing program for improving sleep quality.

• The Journal of Korean Academic Society of Nursing Education
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• v.6 no.1
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• pp.36-47
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• 2000

The purpose of this study was to evaluate the effect of music therapy on the state anxiety and the vital signs in ophthalmic inpatients experiencing momentary visual disturbance. The patients listened to the music for or over 30 minutes a time for 3 days The subjects for this study were twenty-eights experiencing momentary visual disturbance in ophthalmic department of a hospital in Kwangju. They were assigned to two groups, fourteen to a experimental group and fourteen to a control group. The data were collected from November 22 to December 4, 1999 by means of state anxiety scale questionnaire and measurement of vital signs. The data were analyzed with SPSS programs. The results were as follows; 1. There were significant differences between the two groups on anxiety score after music therapy(t=-2.95 p=.007). 2. The first hypothesis that the experimental group who received music therapy would have less anxiety score than the control group who did not receive music therapy was supported (t=8.98, p=.000). 3. There were no significant differences between the two groups on change of vital signs after music therapy. 4. The second hypothesis that the experimental group who received music therapy would have more relived vital signs than the control group who did not receive music therapy was not supported. In conclusion, music therapy can be effective nursing intervention in decreasing anxiety of ophthalmic in-patients experiencing momentary visual disturbance.

• Journal of East-West Nursing Research
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• v.21 no.1
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• pp.69-77
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• 2015

Purpose: The purpose of this study was to investigate the variance of sleep quality and factors affecting sleep disturbance among patients with percutaneous coronary angiography in a general hospital. Methods: The subjects of this study was comprised of 101 patients with percutaneous coronary angiography in a general hospital located in B city. Data were collected by a structured questionnaire from November to December 2013. The data were analyzed with descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient and stepwise multiple regression. Results: The levels of the participants' sleep quality and sleep disturbance were 4.35 and 5.91 in order of each out of the total score, 10. There was no significant difference in the quality of sleep between intensive care unit and internal medicine unit. Factors influencing sleep quality were 'uncomfortable bed, gown and pillow'(${\beta}=-.279$, p=.003), 'living alone'(${\beta}=-.273$, p=.003), and 'toilet problem' (${\beta}=-.222$, p=.016), which explained 21.5% of the variance (F=10.03, p<.001). Conclusion: The results of this study will provide a basis for improving the sleep quality of patients with percutaneous coronary angiography.

• Journal of Oral Medicine and Pain
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• v.26 no.4
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• pp.369-376
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• 2001

Objectives : The purposes of the study was to evaluate cephalometric characteristics in snorers and patients with obstructive sleep apnea (OSA) and to see any relationships between the cephalometric measurements and respiratory disturbance indices (RDI). Materials and Methods : Twelve snoring patients, 11 patients with OSA, and 10 normal subjects were included for the study. After taking a screening sleep study for a night to obtain RDI, $SaO_2$, and snoring index, a detailed cephalometric analysis was conducted to obtain SNA, SNB, SN-MP, IAS, MAS, SPAS, SAAS, Mn-H, and PNS-P. All the data were compared between groups. For a group including 12 snoring patients and 11 OSA patients, correlation coefficients were calculated between respiratory disturbance index and each item of cephalometric measurements. Results : The mandible and the maxilla are retropositioned. The oropharyngeal and hypopharyngeal airway is reduced in area and is a factor that could produce or enhance OSA symptoms. The hyoid bone is displaced inferiorly. The soft palate is significantly elongated. Conclusions : These data suggest that cephalometric evaluation could be useful to evaluate snoring and OSA patients, and to assist with the planning treatment for improvement of upper airway patency.

• Journal of Korean Clinical Nursing Research
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• v.14 no.2
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• pp.115-126
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• 2008

Purpose: This study was aimed to develop an aromatherapy hand massage program, and evaluate the effects of aromatherapy hand massage on cognitive function, sleep disturbance and problematic behaviors of elderly with dementia. Method: The research design was a nonequivalent control group non-synchronized quasiexperimental study. Aromatherapy hand massage was administrated to experimental groupI for 2 weeks, jojoba oil massage were administrated to experimental groupII for 2 weeks, and no treatment for control group for 2 weeks. Data were analyzed using the $x^2-test$, ANOVA, ANCOVA and $Scheff{\acute{e}}$ test in the SPSS 12.0 program. Results: Experimental group I showed significant changes in sleep disturbance and problematic behaviors compared to those in experimental groupII or control group. Conclusion: Aromatherapy hand massage program is found effective on sleep disturbance and problematic behaviors of elderly with dementia.