• 대한간호학회지
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• 제32권3호
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• pp.317-326
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• 2002

The purpose of this study was to verify the effect of aromatherapy on the stress response in menstrual period. Method: A randomized, single-blind, pretest- posttest design was used. The study subjects were 60 college women with dysmenorrhea and they were randomized into 3 groups, experimental, 1st control(placebo) and 2nd control group. The researchers massaged treatment oil(3% dilution essential oil of Lavender, Clary sage and Rose) into the abdomen of experimental group. The placebo group used almond oil(carrier oil) instead, and the 2nd control group did not give any treatment. Baseline data including pre-treatment stress response score were obtained on the first day of usual period. Aromatherapy provided for about 7 days until the next cycle began. Post-treatment stress responses were measured by 94 item SOS(symptom of stress) scale on the first day of the cycle. Results: As a results, the stress response score of experimental group was significantly lower than two control groups. And there was no significant difference in stress responses of two control groups. Conclusion: The results show aromatherapy using selected essential oils to be an effective intervention for stress response during menstruation.

• 한국지반공학회지:지반
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• 제6권4호
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• pp.33-42
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• 1990

정적관입저항 또는 선단지지말뚝의 선단지지력을 해석함에 있어서는 유효수직응력이 기준음력으로 사용되어 왔다. 그러나 정적관입저항은 유효수직응력보다 원위치 유효수평응력에 관계된다는 것이 많은 실험연구결과로부터 보고 되었다. 이와같은 문제점을 규명하기 위하여 기 보고된 실험결과를 다시 분석하였으며 실험실에서의 관입시험이 실시되었다. 연구결과 정적관입저항은 유효수직 응력과 유효수평응력 모두에 영향을 받는 것으로 나타나고 있으며 해석시에는 평균주응력이 기준응력으로 사용되어야 함을 결론 지을 수 있었다.

• 대한한의학회지
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• 제25권2호
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• pp.173-183
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• 2004

Objectives : Oxidative stress can induce negative responses such as growth inhibition or cell death by necrosis or apoptosis due to the intensity of the oxidative stress, as well as positive responses such as cellular proliferation or activation. We examined the effect of Jihwangeumja on this process. Methods and Results : We analyzed the influence of oxidative stress and agents that modify its effect in human umbilical vein endothelial cell (HUVEC). Oxidative stress was induced by $B_2O_2$. With induced oxidative stress the results obtained indicate that it has a harmful effect over cell function and viability, and that this effect is dose and time dependent. When oxidative stress increased, Jihwangeumja reduced cell damage and had protective functions. $B_2O_2$, induced the apoptosis of HUVEC through the activation of intrinsic caspases pathway as well as mitochondrial dysfunction. A significant increase in cell survival was observed in culture cells with oxidative stress when they were treated with Jihwangeumja. Conclusions : These results suggest that Jihwangeumja may be potentially useful to treat HUVEC against oxidative damages mediated by modulation of caspase protease and mitochondrial dysfunction.

• 한국안전학회지
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• 제25권5호
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• pp.44-53
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• 2010

Recently, the external prestressed concrete structures are increasingly being built. The mechanical behavior of prestressed concrete beams with unbonded tendon is different from that of normal bonded PSC beams in that the increment of tendon stress was derived by whole member behavior. By this reason, the ultimate stress of external tendon is smaller than that of bonded tendon or internal unbonded tendon. However, in the domestic and abroad code, the equation of ultimate stress of external tendon is not suggested yet, and the equation of ultimate stress of internal unbonded tendon is used instead of that of external tendon. Therefore, in this paper, after effective variables of ultimate stress of external tendon were analyzed, the analytical equation of ultimate stress of external tendon was proposed. And the reasonable coefficients were proposed by statistical work of test results of 25 beam with external tendon. Finally, the practical proposed equation of ultimate stress of external tendon was proposed with analytical and statistical model. The equation of ACI-318 and AASHTO 1994 were not matched with test results and had no correlations, and the proposed equation was well matched with test results. So the proposed equation in this paper will be a effective basis for the evaluation of external tendons in analysis and design.

• Structural Engineering and Mechanics
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• 제19권6호
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• pp.639-652
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• 2005

In this paper, a full-scale K-joint specimen was tested to failure under cyclic combined axial and in-plane bending loads. In the fatigue test, the crack developments were monitored step by step using the alternating current potential drop (ACPD) technique. Using Paris' law, stress intensity factor, which is a fracture parameter to be frequently used by many designers to predict the integrity and residual life of tubular joints, can be obtained from experimental test results of the crack growth rate. Furthermore, a scheme of automatic mesh generation for a cracked K-joint is introduced, and numerical analysis of stress intensity factor for the K-joint specimen has then been carried out. In the finite element analysis, J-integral method is used to estimate the stress intensity factors along the crack front. The numerical stress intensity factor results have been validated through comparing them with the experimental results. The comparison shows that the proposed numerical model can produce reasonably accurate stress intensity factor values. The effects of different crack shapes on the stress intensity factors have also been investigated, and it has been found that semi-ellipse is suitable and accurate to be adopted in numerical analysis for the stress intensity factor. Therefore, the proposed model in this paper is reliable to be used for estimating the stress intensity factor values of cracked tubular K-joints for design purposes.

• Steel and Composite Structures
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• 제17권2호
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• pp.173-184
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• 2014

This study aimed to theoretical calculate the thermal residual stress in continuous SiC fiber reinforced titanium matrix composites. The analytical solution of residual stress field distribution was obtained by using coaxial cylinder model, and the numerical solution was obtained by using finite element model (FEM). Both of the above models were compared and the thermal residual stress was analyzed in the axial, hoop, radial direction. The results indicated that both the two models were feasible to theoretical calculate the thermal residual stress in continuous SiC fiber reinforced titanium matrix composites, because the deviations between the theoretical calculation results and the test results were less than 8%. In the titanium matrix composites, along with the increment of the SiC fiber volume fraction, the longitudinal property was improved, while the equivalent residual stress was not significantly changed, keeping the intensity around 600 MPa. There was a pronounced reduction of the radial residual stress in the titanium matrix composites when there was carbon coating on the surface of the SiC fiber, because carbon coating could effectively reduce the coefficient of thermal expansion mismatch between the fiber and the titanium matrix, meanwhile, the consumption of carbon coating could protect SiC fibers effectively, so as to ensure the high-performance of the composites. The support of design and optimization of composites was provided though theoretical calculation and analysis of residual stress.

• 한국치위생학회지
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• 제22권4호
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• pp.297-305
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• 2022

Objectives: The purpose of this study is to investigate the effect of depression and stress on subjective oral-related symptoms in adolescen. Methods: This study was based on the 17th Korea Youth Risk Behavior Survey(KYRBS, 2021). A total of 54,848 individuals who responded to items regarding to depression, stress, and subjective oral symptoms were analyzed. Logistic regression analysis was performed to examine subjective oral-related symptoms according to depression and stress, and the analysis results were presented as OR (odds ratio) and 95% CI (confidence interval). Results: Among the subjective oral-related symptoms, 'aching and throbbing teeth' was 1.41 times (95% CI: 1.34-1.49) higher in the group with depression, and 1.40 times (95% CI: 1.31-1.51) was significantly higher in the group with stress. In the case of 'gum pain or bleeding', the symptoms were significantly higher in the group with depression and stress by 1.36 times (95% CI: 1.27-1.45), respectively. Conclusions: As a result of this study, it was found that depression and stress in Korean adolescents had an effect on subjective oral symptoms. Study results suggest that depression and stress in Korean adolescents has an effect on their subjective oral-related symptoms

• 기본간호학회지
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• 제14권1호
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• pp.120-127
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• 2007

Purpose: This study was done to identify the level of stress, hardiness, and professional burnout of intensive care unit (ICU) nurses and to provide basic data for the qualitative improvement of nursing work achievement in the workplace. Method: The data were obtained from 129 ICU nurses through a questionnaire. Results: Stress showed positive correlation with the level of professional burnout and there was negative correlation between hardiness and professional burnout. Nurses in the group with a high level of stress, and a high level of hardiness reported a low level of professional burnout compared to those in the group with a lower level of hardiness (t=-2.60, p= .012). Nurses in the group with a low level of hardiness and a low level of stress showed a lower level of professional burnout than those with a high level of stress (t=3.51, p= .001). Conclusion: The results show that the high level of stress when coupled with a low level of hardiness of ICU nurses results in a high level of professional burnout. For this reason, it is important for nursing administration to support nurses to reduce levels of stress and the resulting burnout in ICU nurses.

• 대한통합의학회지
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• 제12권1호
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• pp.41-48
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• 2024

Purpose : This study aims to understand the effects of job-seeking stress on depression and self-esteem in college students majoring in health science. Methods : In this study, in order to measure college students' employment stress, depression, self-esteem, and social support, a measurement tool was used by modifying and supplementing the questionnaire to suit the purpose and method of this study. The subjects, 210 students (46 men and 164 women) enrolled in colleges located in Busan, had their scores on the Beck depression inventory (BDI), job-seeking stress scale, and self-esteem scale measured. Results : There was a positive correlation between all sub-variables of employment stress, and a negative correlation between employment stress and self-esteem. Additionally, a positive correlation was found between employment stress and depression, and a negative correlation was found between self-esteem and depression. The result taken from the job-stress scale showed that women experienced an overall higher level of stress than men while seeking jobs. Furthermore, in terms of the BDI, men exhibited a higher level of depression than women when subjected to job-seeking stress. Finally, the results from the self-esteem scale reveal that men exhibited less self-esteem than women. Conclusion : A comprehensive review of the study's findings suggested that women had greater job-seeking stress than men. Additionally, it found that, for men, job-seeking stress had a greater impact on depression levels and self-esteem. These results suggest that a higher level of job-seeking stress may lead to higher levels of depression and lower levels of self-esteem. It will be useful to conduct follow-up research by operating self-esteem and depression programs.

• 한국안전학회지
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• 제14권4호
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• pp.43-52
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• 1999

In this study, theoretical stress field analysis near the crack tip under tension-compression loading was performed. The results of the theoretical stress analysis were compared to the results of Finite Element Method(FEM). From this study, generation of tensile residual stress at crack tip was proved after 1-cycle of tension-compression loading, and the fracture toughness and the fracture load of a structure can be decreased by the residual stress.