• Journal of Periodontal and Implant Science
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• v.31 no.4
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• pp.803-810
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• 2001

The purposes of this study were to investigate the relationship between cigarette smoking levels and periodontal status. 199 subjects, consisting of male 127 and female 72, classified by smoking levels and duration were selected: Patients who had smoked for more than 20 cigarettes/day were considered heavy smokers, 10 to 19, moderate smokers; 1-9, light smokers:0, non-smoker. And smokers were divided into ones who had smoked for more than 20 years, 10-19 years, less than 10 years and non-smokers. Heavy smokers and moderate smokers showed significantly greater pocket depths, less clinical attachment levels, more molar furcation involvements, greater alveolar bone loss and higher scores of plaque index than light smokers and non-smokers,(p < 0.05). When the duration of smoking was considered as a factor, scores of clinical parameters were worse and alveolar bone loss were significantly greater in long-term smokers, who had smoked for more than 20 years. In conclusion, cigarette smoking is associated with periodontal status.

• Korean Journal of Biological Psychiatry
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• v.13 no.1
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• pp.26-31
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• 2006

Object : To evaluate how the therapeutic factors affect post-discharge course of patients with schizophrenia, we analyzed relationship between each therapeutic factor and outcome of inpatients with schizophrenia in Hanyang University Hospital. Methods : This study is a retrospective report. Subjects were schizophrenic inpatients who were discharged from Hanyang University Hospital from January 1, 2003 through December 31, 2004. We obtained demographic and clinical data from review of inpatient and outpatient charts. Results : We analyzed the records of 104 patients with schizophrenia(44 males and 60 females). Patients who had longer first admission days have fewer number of readmission. There were no significant correlation between psychiatric rehabilitation and course of schizophrenia. Courses, such as duration of outpatient department follow-up and number and duration of rehospitalization, did not differ according to the existence of extrapyramidal symptoms or types of antipsychotics prescribed. Conclusion : Among the therapeutic factors, longer duration of the first admission only affected better post-discharge course of patients with schizophrenia.

• Perspectives in Nursing Science
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• v.9 no.2
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• pp.94-101
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• 2012

Purpose: The purpose of this study was to examine the relationship between glucose control, diabetes self-care and depression in community dwelling older adults with type 2 diabetes mellitus. Methods: The cross-sectional survey data of 148 older adults at a senior center were analyzed in this study. We collected data on diabetes self-care, depression, and demographics by face-to-face interviews. Blood samples for HbA1C were obtained from the participants. Results: The average duration of diabetes for the participants was $10.6{\pm}9.31$ years. Fifty percent of the participants had HbA1c higher than 7.0% (mean 7.179%). The level of diabetes self-care was related to depression (r=-.225, p<.01). HbA1c was positively related with the duration of diabetes diagnosis (r=.224, p<.01). The only sub-dimension of diabetes self-care that was related to depression was exercise (r=-.307, p<.01). Conclusion: Only half of the community dwelling older adults with type 2 diabetes had an optimal level of diabetes control. Supported by the evidence, the longer the duration of diabetes since the initial diagnosis, the poorer the glucose control was. Identification and intervention for depression in people with diabetes should be considered to improve diabetes self-care, especially to perform more exercise.

• International Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.58-61
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• 2015

Under the background of combustion instability in solid rocket motor, to study the relationship between pressure oscillations and dynamic process of propellant flames, it is necessary to simulate an oscillation environment with certain frequency, amplitude and duration. This paper presents an experimental installation of pressure oscillation based on pulse-driving technique, with which pressure oscillations features under different pulse-driving conditions were compared and analyzed. For the pulse-driver applied in this paper, a pressure oscillation with 0.15s-0.5s duration, 179Hz-210Hz first order frequency, 0.04MPa-0.35MPa amplitude is simulated. The test results show that an oscillation with higher frequency and lager amplitude can be obtained when pulse-driver is installed on the top of the installation cavity, while on the side, an oscillation with a longer duration and approximate cavity natural frequency can be simulated.

• Korean Journal of Occupational Health Nursing
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• v.20 no.3
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• pp.356-364
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• 2011

Purpose: This descriptive study was to examine the effect factors on health promotion lifestyle of shift work nurses. Methods: The 418 working nurses who completed questionnaires with consent were analysed. Results: The average level of health promotion lifestyle of shift work nurses was 2.21 and it was significantly lower than 2.36 of fixed work nurses. In shift work nurses, the highest health promotion lifestyle was personal relationship of 2.79 and the lowest was physical activity of 1.58. The young, shorter shift work duration, unmarried and general nurses were evaluated as not-healthy diet. The old, longer shift work duration and married showed less physical activity. Less self-efficacy and more job stress, depression, fatigue showed lower health promotion lifestyle. Conclusion: Self-efficacy on health behavior of shift work nurses was the most effective factor on all areas of health promotion. Therefore, we need to develop a health promotion program including self-efficacy encouragement. We suggest that this program be more effective when more precisely characterized according to age, marital status, shift work duration, job position, and psychological problems such as depression and fatigue.

• Journal of Home Health Care Nursing
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• v.12 no.2
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• pp.87-101
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• 2005

Purpose: The purpose this study was to investigate the relationship between self-care performance and influential factors in hemodialysis patients. Method: The subjects of this study were 102 hemodialysis outpatients who had been visiting C University Hospital in Seoul. The data were collected through the scale of self care, self efficacy family support, daily living activity and hope from the 1st to 31st of December 2004. The collected data were analysed using SPSS PC Win 10.0. Result: The average score of self-care performance of subjects was $3.2\pm0.4$ points(4points scale) and significantly different among groups according to age and duration of dialysis. Self care performance of subjects was in a significant positive correlation with family support and hope. Factors affecting self care performance of subjects were family support, duration of hemodialysis, age and daily living function, and the explanatory power of these factors was 31.4%. Conclusion: These findings indicate that is necessary to enhance family support, to develope and apply self-care education programs in consideration of duration of dialysis and age, to have hope-giving communication with patients and their families, and to provide nursing interventions for maintaining patients' daily living function in order to improve the self care performance of hemodialysis patients

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.1
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• pp.39-47
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• 2004

The objective of this study is to analyse the spray characteristics according to the injection duration under ambient pressure condition and to investigate the relationship between vorticity and entropy for controlling diffusion process that is the most important thing during the intake stroke injection process. Therefore, the spray velocity was obtained by using the PIV method that has been an useful optical diagnostics technology, and vorticity calculated from spray velocity component with vorticity algorithm. In addition, the homogeneous diffusion rate of spray was quantified by using the entropy analysis based on the Boltzmann's statistical thermodynamics. From these method, we found that as injection duration increases, spray velocity increases and the location of vortex is moved to the downstream of spray. In the same condition, as the entropy decrease, mean vorticity increases. This means that the concentration of spray droplets caused by the increase of injection duration is more effective than the increase of momentum dissipation.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.1
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• pp.33-41
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• 2004

We developed a cardiac cell model to explain the phenomenon of mechano-electric feedback (MEF), based on the experimental data with rat atrial myocytes. It incorporated the activity of ion channels, pumps, exchangers, and changes of intracellular ion concentration. Changes in membrane excitability and $Ca^{2+}$ transients could then be calculated. In the model, the major ion channels responsible for the stretch-induced changes in electrical activity were the stretch-activated channels (SACs). The relationship between the extent of stretch and activation of SACs was formulated based on the experimental findings. Then, the effects of mechanical stretch on the electrical activity were reproduced. The shape of the action potential (AP) was significantly changed by stretch in the model simulation. The duration was decreased at initial fast phase of repolarization (AP duration at 20% repolarization level from 3.7 to 2.5 ms) and increased at late slow phase of repolarization (AP duration at 90% repolarization level from 62 to 178 ms). The resting potential was depolarized from -75 to -61 mV. This mathematical model of SACs may quantitatively predict changes in cardiomyocytes by mechanical stretch.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.1
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• pp.55-70
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• 2019

The phase properties of ground acceleration records from Mw 5.5~6.5 earthquakes are analyzed. The interrelationships between phase properties and significant durations, as well as PGA, are clarified through both of theoretical and empirical approaches. The probabilistic characteristics of phase information is also discussed based on previous studies and it is shown that circular normal distribution is the most appropriate probability distribution for the phase angle and phase difference. Whereas those variates can be modeled by Gaussian random variables. From the survey results on the frequency dependency of the phase statistics, a simple model is introduced, which is possible to express the frequency dependency of phase information. It is also shown that the significant duration can be controlled by appropriately chosen standard deviation of phase difference for 4~8Hz frequency band and additional consideration of phase scattering in higher frequency band through a series of Monte Carlo simulations. The source of phase scattering effect is also pointed out and discussed.

• Journal of Environmental Science International
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• v.9 no.4
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• pp.303-309
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• 2000

The relationship between air temperature and sea surface temperature and studied using the daily air temperature and sea surface temperature data for 25 years (1970~1994) at 9 coastal stations in Korea. Seasonal variations of air temperature have larger amplitudes than those of sea surface temperature. The seasonal variations of air temperature leads those of sea surface temperature by 2 to 3 weeks. The anomalies of sea surface temperature and air temperature with time scales more than 1 month are more ghighly correlated than those of short term, with time scales less than 1 month. Accumulated monthly anomalies of sea surface temperature and air temperature for 6 months shwoed higher correlation than the anomailes of each month. The magnitudes of sea surface temperature and air temperature anomalies are related with the duration of anomalies. Their magnitudes are large when the durations of anomalies are long.