• 한국세라믹학회지
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• 제54권1호
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• pp.33-37
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• 2017

Single phase niobium nitride (NbN) coatings were deposited using asymmetric bipolar pulsed dc sputtering by varying pulse frequency and duty cycle of pulsed plasmas. Crystal structure, microstructure, morphology and mechanical properties were examined using XRD, FE-SEM, AFM and nanoindentation. Upon increasing pulse frequencies and decreasing duty cycles, the coating morphology was changed from a pyramidal-shaped columnar structure to a round-shaped dense structure with finer grains. Asymmetric bipolar pulsed dc sputtered NbN coatings deposited at pulse frequency of 25 kHz is characterized by higher hardness up to 17.4 GPa, elastic modulus up to 193.9 GPa, residual compressive stress and a smaller grain size down to 27.5 nm compared with dc sputtered NbN coatings at pulse frequency of 0 kHz. The results suggest that the asymmetric bipolar pulsed dc sputtering technique is very beneficial to reactive deposition of transition-metal nitrides such as NbN coatings.

• 동의생리병리학회지
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• 제24권3호
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• pp.525-532
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• 2010

Dypepsia is the most common gastrointestinal disease and mainly occurs by stress or food. According to the cause of dyspepsia, the clinical characteristics and the curative process are different in patients. The purpose of this study is to compare acute dyspepsia patients depending on food factor and stress factor. For this study, we analyzed the cause, and the symptoms of 59 acute dyspepsia patients and divided them into two groups: one group is 27 acute dyspepsia patient group caused by stress factor (stress factor group). The other group is 32 acute dyspepsia patient group caused by food factor (food factor group). In addition, we carried out HRV test and compared HRV index between two groups. There was no significant difference in past illness involved in gastrointestinal tract diseases between two groups. There were big differences in the frequency of chest discomfort, thurst, lack of appetite, and exhaustion after meals between two groups. There were many changes of tongue fur in food factor group. But there were many changes of tongue body in stress factor group. The pulse pattern is mostly wiry in stress factor group. But, The pulse pattern is mostly slippery in food factor group. HF, TP were significantly lower than food factor group in stress factor group, it means autonomic nerve system was more suppressd in stress factor group than food factor group. Food factor group improved sooner than stress factor group. This study presented the clinically different characteristics (past medical history, symptoms, tongue diagnosis, pulse pattern, curative process) of acute dyspepsia depending on food factor and stress factor. Thus, it provides the necessity of oriental medical diagnosis and treatment called pattern identification for acute dyspepsia.

• 대한간호학회지
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• 제29권4호
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• pp.855-869
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• 1999

The purpose of this study was to test the effectiveness of self-management relaxation training through biofeedback and progressive muscle relaxation methods. The effectiveness of the experimental methods was tested by measuring the degree of symptoms of stress (SOS), the McNair's profile of Mood States (POMS), the levels of ephinephrine, norepinephrine, pulse rate, blood pressure and natural killer cells. The subjects of this study were sixty six nursing students divided into four groups : two groups were the biofeedback and progressive muscle relaxation groups, the other two groups served as control groups. One was a group of sophomores with no experience at all, the other a junior group without self -management or relaxation training. This study was conducted for eight weeks of clinical practice from April, 26th 1998 to June, 20th 1998. Biofeedback training was done with software developed by J&J company (1-410 form for abdominal respiration training). Progressive muscle relaxation training was done with u audiotape recorded according to Jacobson's Theory. The data were analyzed with frequencies, means, and analysis of covariance using the SPSS program and the significance level of statistics was 5%. The results of the study are : 1) The importance of clinical practice stress reduction is shown in that the level of symptoms of stress in the experimental groups in clinical practice was higher than in the group receiving only a lecture. 2) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in reducing the symptoms of stress under the clinical practice stress conditions. 3) The effectiveness of the biofeedback training relaxation method to reduce symptoms of stress was higher than that of progressive muscle relaxation. 4) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in reducing stressful mood states. 5) The relaxation training methods of biofeedback and progressive muscle relaxation were not effective in reducing epinephrine and norepinephrine levels. 6) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in increaing the number of natural killer cells. 7) The relaxation training methods of biofeedback and progressive muscle relaxation were effective in decreasing high systolic and diastolic values of blood pressure and high pulse rates. In summary, the relaxation methods of biofeedback and progressive muscle relaxation in reducing clinical practice stress were effective in lowering the level of symptoms of stress and the profile of stressful mood states. They were also effective in lowering high blood pressure and pulse rates. The relaxation methods were effective in increasing the number of natural killer cells as part of the immune function. However, relaxation methods were not effective in reducing the catecholamine level. The biofeedback training method for reduction of symptoms of stress was more effective than the progressive muscle relaxation method.

• 기본간호학회지
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• 제6권2호
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• pp.169-184
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• 1999

The purpose of this study was to identify the effects of breathing biofeedback training on the stress of nursing students in clinical practice. The research design was a nonequivalent control group pretest-posttest design. The subjects of this study were 39 nursing students from the College of Nursing of K University. The study was conducted from July 20 to September 3, 1998. The subjects were assigned to one of two groups : the experimental group (19 students), and the control group (20 students). The breathing biofeedback training was performed 12 times with the experimental group. The level of psychological stress was measured using the State Anxiety Inventory, Profile of Mood State, and Visual Analogue Stress Scale. The level of physiological stress was measured using pulse rate and blood pressure. The data were analyzed using descriptive statistics, $x^2-test$, t-test, and repeated measures of ANOVA. The results of study are as follows : 1) State anxiety scores were not significantly different between the experimental group and the control group after the biofeedback training. 2) Profile of mood state scores were not significantly different between the experimental group and the control group after the biofeedback training. 3) Visual Analogue Stress Scale scores were significantly different between the experimental group and the control group after the biofeedback training(F=11.68, p=0.002). 4) Pulse rates were not significantly different between the experimental group and the control group after the biofeedback training. 5) Systolic blood pressures were significantly different between the experimental group and the control group after the biofeedback training(F=5.44, p=0.025). 6) Diastolic blood pressures were not significantly different between the experimental group and the control group after the biofeedback training. On the basis of the above findings, the following recommendations for further study are made ; 1) Identification of the effects of breathing biofeedback training at times of high stress during clinical practice. 2) Identification fo the effects of stress reduction according to the frequency of the breathing biofeedback training.

• 한국환경보건학회지
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• 제44권5호
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• pp.502-513
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• 2018

Objectives: Stress hormone (cortisol) can be used to analyze psychological and physiological changes and healing effects before and after in blood and saliva. Here it is applied to scientifically validate the effects of the healthy forest experience in Deogyusan Mountain National Park. Methods: A healthy forest experience program was provided to college students (males and females) at Deogyusan National Park. Stress, hormones (cortisol), blood pressure, pulse, oxygen saturation and stress, anxiety, and depression were measured. This study was designed to objectively analyze the effects of stress hormones before and after. Results: Depression, stress, anxiety, and satisfaction with the forest experience program in Deogyusan National Park were very high in reliability in terms of Cronbach's Alpha: depression scored 0.910, stress 0.558, anxiety 0.934, program satisfaction 0.826, and program effectiveness 0.894. Conclusions: In this study, we utilized the Healthy Forest Experience Program and the 'Health and Medical Center Health Record Book' of the Health Forest Experience Program (Ministry of Environment's Environmental Education Certification Program). In the future, we will seek ways to utilize saliva since it is easier to collect than blood samples and apply the stress hormone cortisol as a saliva authentication program. In addition, by implementing ecological welfare programs in which nature and human beings coexist through systematic preservation and restoration, the national park management can utilize ecological, scenic and cultural services wisely. We expect to be able to provide exploration and welfare services.

• 한국전기전자재료학회논문지
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• 제28권6호
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• pp.360-364
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• 2015

Electronic systems based on solid state devices have changed to be more complicated and miniaturized as the electronic systems developed. If the electronic systems are exposed to HPEM (high power electromagnetics), the systems will be destroyed by the coupling effects of electromagnetic waves. Because the HPEM has fast rise time and high voltage of the pulse, the semiconductors are vulnerable to external stress factor such as the coupled electromagnetic pulse. Therefore, we will discuss about malfunction behavior and DFR (destruction failure rate) of the semiconductor caused by amplitude and repetition rate of the pulse. For this experiment, the pulses were injected into the pins of general purpose IC due to the fact that pulse injection test enables the phenomenon after the HPEM is coupled to power cables. These pulses were produced by pulse generator and their characteristics are 2.1 [ns] of pulse width, 1.1 [ns] of pulse rise time and 30, 60, 120 [Hz] of pulse repetition rate. The injected pulses have changed frequency, period and duty ratio of output generated by Timer IC. Also, as the pulse repetition rate increases the breakdown threshold point of the timer IC was reduced.

• 여성건강간호학회지
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• 제16권4호
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• pp.336-347
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• 2010

Purpose: The purpose of this study was to identify the effect of relaxation therapy on state anxiety, preterm labor stress, blood pressure, skin temperature, pulse rate of pregnant women with preterm labor and heart rate of their babies. Methods: The participants were 55 pregnant women with preterm labor who hospitalized from May, 2009 to January, 2010. 29 participants were assigned to experimental group and the other 26 participants to control group. All of them were not have any other complications except preterm labor. The relaxation therapy was applied to the experimental group for 5 days. Data were analyzed by the SPSS/WIN 14.0 program. Results: The state anxiety score and the preterm labor stress score of experimental group were statistically significant lower than those of control group. In addition, the systolic and diastolic blood pressure, pulse rate of experimental group were statistically lower than those of control group. The skin temperature of experimental group was higher than that of control group. However, the fetal heart rate of experimental group was not statistically significant lower than fetal heart rate of control group. Conclusion: From these findings, it is concluded that relaxation therapy may be an effective nursing intervention for pregnant women with preterm labor.

• Korean Journal of Acupuncture
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• 제40권2호
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• pp.44-53
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• 2023

Objectives : This study was conducted to reveal the relationship between multiple factors of traditional Korean Medicine diagnosis and consider the further probabilities of treating people with physical and mental problems not defined as diseases, which is called 'Mibyeong' in traditional Korean Medicine. Methods : 40 healthy participants were included in the observational clinical trial. The participants were asked to complete health questionnaires (e.g. State-Trait Anxiety Inventory, Pittsburgh Sleep Quality Index, Stress Response Inventory) and they went through a traditional diagnosis process, including four stages of diagnosis (looking, listening/smelling, inquiring, and pulse taking), by a Korean Medicine doctor. Both the Korean Medicine doctor and an artery tonometry device performed the pulse diagnosis. Results : Although all participants were healthy people with no history of disease, more than half of participants had a problem related with severe level of fatigue (n=19), sleep disturbance (n=26) and stress (n=27) status according to the related questionnaires. Participants diagnosed with phlegm syndrome by the Korean Medicine doctor showed significantly greater score in phlegm pattern questionnaires than participants who were not. However, there was little agreement between the doctor's pulse diagnosis and radial artery tonometry results. Conclusions : We conducted a pulse diagnosis and measured health-related information along with the traditional Korean Medicine diagnose procedure, including four stages of diagnosis, and we found a linkage between diagnosis of phlegm and the phlegm pattern questionnaire score. The results suggest that a number of healthy participants, with no disease diagnosed, have Mibyoung symptoms which need further clinical management. Thus, we suggest that Mibyoung management programs based on qualified diagnosis tools and traditional Korean medicine diagnosis procedures be developed, and that future research using various diagnostic tools be carried out on a large population.

• Steel and Composite Structures
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• 제36권3호
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• pp.249-259
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• 2020

In this work, a novel three-dimensional model in the generalized thermoelasticity for a homogeneous an isotropic medium was investigated with diffusion, under the effect of thermal loading due to laser pulse in the context of Green-Lindsay theory was investigated. The normal mode analysis technique is used to solve the resulting non-dimensional equations of the problem. Numerical results for the displacement, the thermal stress, the strain, the temperature, the mass concentration, and the chemical potential distributions are represented graphically to display the effect of the thermal loading due to laser pulse and the relaxation time on the resulting quantities. Comparisons are made within the theory in the presence and absence of laser pulse.

• 한국표면공학회지
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• 제22권4호
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• pp.197-206
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• 1989

The Composition and throwing power-of Pb-Sn alloy deposits are investigated in tems of the pulse parameters in pulse plating. Microhardness and intermal srress of alloy deposots are measured. The current efficiency of pulse plating is lower than that of D.C.plating while cathode overpotential and macro-throwing power noticebly increase with increasing peak current density. The Pb content of P.C. plated alloy deposits with increasing average current density, is relatively lower than of D.C. plated deposits at the same average current density. The internal stress of Pb-Sn alloy is not detected and the microhardness are 9.0kg/mm2 and 11kg/mm2 for D.C. plated P.C. plated deposits, respectively.