• Journal of the Korean Home Economics Association
• /
• v.35 no.6
• /
• pp.87-99
• /
• 1997

This study intends to find the effects of children's stress level and coping behaviors on their stress symptoms. The subjects were 840 4-6th grade children in Seoul. The data were analyzed by frequencies, percentages, means, ANOVA, stepwise regression and Cronbach's α. The regression model explained 46% of children's stress symptoms which were affected by coping behaviors(emotional aggression, positive revaluation, seperation for emotional relaxation) and by stressors(children's social-life, individual factors, school-life).

• Proceedings of the KSR Conference
• /
• 2005.11a
• /
• pp.1130-1137
• /
• 2005

This paper addresses the mathematical model of the long-term track tamping scheduling problem in the railway system. The proposed model is analyzed in problem size, then three solution approaches (relaxation, decomposition, and heuristic) are presented at the sketch level.

• Bulletin of the Korean Chemical Society
• /
• v.19 no.6
• /
• pp.628-634
• /
• 1998

The properties of the n-type impurities nitrogen and phosphorus in diamond have been investigated by means of electronic band structure calculations within the framework of the semiempirical extended Huckel tight-binding method. For diamond with the nitrogen and phosphorus substitutional impurities, calculated density of states shows the impurity level deep in the band gap. This property can be derived from the substantial <111> relaxation of the impurity and nearest-neighbor carbon atoms, which is associated with the population of an antibonding orbital between them. The passivated donor property of the P-vacancy complex which lies deep in the gap is also discussed.

• Progress in Superconductivity and Cryogenics
• /
• v.5 no.1
• /
• pp.21-26
• /
• 2003

We designed and constructed a multichannel superconducting quantum interference device (SQUID) magnetometer system to measure magnetic fields from the human brain. We used a new type of SQUID, the double relaxation oscillation SQUID (DROS). With high flux-to-voltage transfers of the DROS, about 10 times larger than the dc SQUIDs, simple flux-locked loop circuits could be used for SQUID operation. Also the large modulation voltage of the DROS, typically being 100 $mutextrm{V}$, enabled stable flux-locked loop operation against the thermal offset voltage drift of the preamplifier. The magnetometers were fabricated using the Nb/AlOx/Nb junction technology. The SQUID system consists of 37 signal magnetometers, distributed on a semispherical surface, and 11 reference channels were installed to pickup background noises. External feedback was used to eliminate the magnetic coupling with the adjacent channels. The liquid helium dewar has a capacity of 29 L and boil-off rate of about 4 L/d with the total 48 channel insert. The magnetometer system has an average noise level of 3 fT/√Hz at 100 Hz, inside a shielded loon, and was applied to measure auditory-evoked fields.

• Korean Journal of Artificial Intelligence
• /
• v.6 no.2
• /
• pp.17-22
• /
• 2018

According to the World Health Organization, the top 10 causes of death worldwide include heart disease. Heart diseases include coronary disease, which induces acute myocardial infarction. Ticagrelor drugs are being used to treat acute alliances, but it has become difficult to breathe due to the drugs. In a related study, Tobias predicted that uric acid causes acute respiratory distress independently of other factors, including BNP. And in the Ahmad study, serum uric acid numbers were related to the left ventricle depending on the level of uric acid. Experimental data are data used after 155 patients who received coronary intervention took ticagrelor. The research methods were leveraged by gradient decent algorithm and linear regression. In order to avoid overfitting in the experiment, training data and test data were separated into 70 and 30 percent respectively. The experimental results lacked the predictability of other attributes except DT in the correlation coefficient and crystal coefficient. However, all attributes related to dyspnea other than DT are determined to be related to causing relaxation of the heart in the left ventricle. Therefore, the attribute causing dyspnea is determined to be an attribute causing relaxation of the heart of the DT and left ventricle.

• Journal of Veterinary Clinics
• /
• v.21 no.3
• /
• pp.291-297
• /
• 2004

Aminoglycosidic antibiotics have multiple effects on muscle. For example, they have been shown to block L-type $Ca^{2+}$ channels in vascular smooth muscle, cardiac muscle and skeletal muscle. Possibly as a consequence of this effect on $Ca^{2+}$ influx, they have been shown to decrease the contractility of cardiac muscle (gentamicin). The present study evaluated the effects of gentamicin on blood pressure, vasorelaxation and left ventricular pressure. Gentamicin(10, 20, 40mg/kg) produced dose-dependent blood pressure lowering in rat. The pretreatment of MgSO$_4$ and imipramine (Na$^{+}$-Mg$^{2+}$ exchange inhibitor) had no effect in gentamicin-induced hypotension. However, the gentamicin-induced hypotension was significantly potentiated in the preincubation of verapamil or nifedipine (L-type $Ca^{2+}$ channel blockers), and was significantly attenuated by CaCl$_2$ and was slightly attenuated by caffeine (phosphodiesterase inhibitor). Gentamicin (10, 30, 100$\mu$g/m1) did not have an effect on relaxation of phenylephrine-precontracted aortic rings but high concentration of gentamicin(100, 300$\mu$g/ml) relaxed KCl-precontracted aortic rings, which relaxation was potentiated by treatment of nifedipine. Whereas gentamicin markedly decreased left ventricular developed pressure (LVDP) in perfused heart. These data suggest that gentamicin has significant blood pressure lowering of the rat, which seems to be mediated by calcium channel-sensitive pathway and blood $Ca^{2+}$ level may be important role in this response.

• Journal of Korean Critical Care Nursing
• /
• v.7 no.2
• /
• pp.34-44
• /
• 2014

Purpose: The purpose of this study was to determine the factors related to airway failure during endotracheal intubation among patients with and without predicted airway difficulty. Methods: Medical records were examined retrospectively. 329 patients who were admitted to the general ward and underwent endotracheal intubation were included. The incidence of airway failure in the two groups was investigated. Results: The group predicted to have airway difficulty consisted of 79 patients (24.0%) and the group without airway difficulty, 250 (76.0%). The number of cases of airway failure was 50 (15.2%). The factors that were associated with airway failure in the group with predicted airway difficulty were the jaw relaxation score, Cormack-Lehane score, and the device of the first endotracheal intubation attempt. The factors that were associated with the airway failure in the group predicted not to have airway difficulty were the induction agent, jaw relaxation score, Cormack-Lehane score, level of training of the personnel with the first endotracheal intubation success, and the device of the first endotracheal intubation attempt. Conclusion: The prediction of airway difficulty during endotracheal intubation was not effective; however, it was meaningful from the perspective of patient safety.

• Transactions of Materials Processing
• /
• v.11 no.6
• /
• pp.529-537
• /
• 2002

A series of load-relaxation tests and tensile tests were conducted to study the high temperature deformation mechanism of fine duplex gamma TiAl alloy at temperatures ranging from 800 to 105$0^{\circ}C$. Results of load relaxation test showed that deformation behavior at a small imposed strain ($\varepsilon$≒0.05) was dominated by dislocation glide and dislocation climb. To investigate the deformation behavior at a large amount of strain, the processing map was constructed using a dynamic materials model. Two domains were characterized in the processing map obtained at a strain level of 0.6. One domain was found at the region of 98$0^{\circ}C$ and $10^{-3}/sec$ with a peak efficiency of 48%, which was identified as a domain of dynamic recrystallization from the microstructural observation. The order was observed at the region of 125$0^{\circ}C$ and $10^{-4}/sec$ with a peak efficiency of 64%. The strain rate sensitivity measured indicates that the material was deformed by the superplasticity in the region.

• Korean Journal of Materials Research
• /
• v.20 no.3
• /
• pp.161-166
• /
• 2010

The ac, dc conductivity and dielectric properties of $DyCoO_3$ were reported in the temperature range of 77 - 300K and in the frequency range of 20 Hz - 100 kHz. It was observed that at low temperature, ac conductivity is much higher than dc conductivity and the hopping carrier between localized states near the Fermi level was the dominant loss mechanism. A comparison of the measured ac conductivity $\sigma(\omega)$ was made with some of the models of hopping conductivity of the proposed earlier in the literature. It was observed that in $DyCoO_3$ the measured ac conductivity, over the entire frequency and temperature region, can be explained reasonably well by assuming two contributions $\sigma_1(\omega)$ and $\sigma_2(\omega)$ to the measured $\sigma(\omega)$. The first, $\sigma_1(\omega)$, which dominates at low temperature, may be due to impurity conduction in a small polaron; the second, $\sigma_2(\omega)$, which dominates at higher temperatures, depending on the frequency of measurements, may be due to the hopping of a small polaron and is reasonable for the dielectric relaxation peak.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.12
• /
• pp.3943-3959
• /
• 2022

People are constantly exposed to stress and anxiety environment, which could contribute to a variety of psychological and physical health problems. Therefore, it is particularly important to identify psychological stress in time and to find a feasible and universal method of stress reduction. This research investigated the influence of different music, such as relaxation music and natural rhythm music, on stress relief based on Electroencephalogram signals. Mental arithmetic test was implemented to create a stressful environment. 23 participants performed the mental arithmetic test with and without music respectively, while their Electroencephalogram signal was recorded. The effect of music on stress relief was verified through stress test questionnaires, including Trait Anxiety Inventory (STAI-6) and Self-Stress Assessment. There was a significant change in the stress test questionnaire values with and without music according to paired t-test (p<0.01). Furthermore, a model based on Transformer for stress level classification from Electroencephalogram signal was proposed. Experimental results showed that the method of listening to relaxation music and natural rhythm music achieved the effect of reducing psychological stress and the proposed model yielded a promising accuracy in classifying the Electroencephalogram signal of mental stress.