• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 1999.04a
• /
• pp.23-23
• /
• 1999

후류손실을 가지는 혼합 전단층에 대하여 밀도변화가 없는 유동 및 밀도변화가 있는 유동의 선형 불안정성 해석을 수행하였다. 기본 유동의 속도장 및 밀도장은 tanh 함수를 사용하였으며, Gaussian 형태의 해석적 함수를 사용하여 두 유동을 분리시키는 평판 바로 다음에 존재하는 후류 손실 유동을 포함시켰다. 공간적 선형 불안정성 해석을 수행하여 불안정성 모드의 성장률과 파장속도를 주파수의 함수로서 구하였다. 해석 결과로부터 후류 손실을 가지는 혼합층은 sinuous 모드와 varicose 모드의 두 개의 불안정성 모드를 가짐을 알았다. 밀도가 균일한 경우에는 varicose 모드보다 sinuous 모드가 지배적이다. 밀도가 균일한 경우에는 varicose 모드보다 sinuous 모드가 지배적이다. 밀도구배가 존재하나 빠른 자유유동의 밀도가 높은 경우에는 밀도가 균일한 경우와 마찬가지로 sinuous 모드가 지배적인 모드가 된다. 그러나 느린 자유 유동의 밀도가 높은 경우에는 밀도장의 두께가 속도장의 두께보다 상대적으로 얇아지면 varicose 모드가 sinuous 모드보다 더욱 불안정하여질 수 있다. varicose 모드와 sinuous 모드의 성장률이 비슷한 밀도장의 두께에서는 두 불안정성 모드가 주파수 변화에 따라 분지 되어지는 경향을 보인다.

• Anxiety and mood
• /
• v.19 no.2
• /
• pp.27-36
• /
• 2023

Interest in anxiety has a long history, and this topic has played a significant role in the field of mental health. The concept of anxiety has evolved diversely over time and across cultures, influencing our understanding, diagnosis, and treatment approaches for anxiety disorders. In this paper, we have reviewed and summarized various concepts and theories related to anxiety that have evolved over several centuries. Furthermore, we have examined how the diagnostic criteria in the DSM (Diagnostic and Statistical Manual of Mental Disorders) have changed within this historical context. A precise understanding of the history of the concept of anxiety and anxiety disorders is believed to have a positive impact on shaping the future path of anxiety disorders in psychiatry.

• Sleep Medicine and Psychophysiology
• /
• v.6 no.1
• /
• pp.76-84
• /
• 1999

Objectives: A number of studies have shown that sleep deprivation results in reduced vigilance and increased negative affects such as tension, depression and anger. However there are few studies about effects of sleep deprivation on anxiety. The purpose of this study was to investigate the effects of 40 hour sleep deprivation on state anxiety, affects, sleepiness and fatigue. The authors also intended to study the effect of trait-anxiety on these psychological variables after sleep deprivation. Methods: Twenty nine subjects(22 men, 7 women, $24.59{\pm}1.35$ years of age) participated in this study. Subjects had no past history of psychiatric disorders and physical illnesses, and had normal sleep-waking cycle without current sleep disturbances. All of the subjects completed sleep dairy for two weeks to exclude some who suffered from chronic sleep deprivation or sleep disturbances. Subjects were instructed to get a normal sleep as usual at night before the study. After awakening, subjects remained awake for 40 hours under continuous surveillance. They completed State-Trait Anxiety Inventory, Index of General Affect, Stanford Sleepiness Scale and Fatigue Questionnaire every three hours, therefore they completed the scales 14 times totally. Subjects were dictated not to take caffeine, alcohol, or any medications on the day of the study. Heavy exercises and naps were restricted too. Results: Sleep deprivation resulted in increased state anxiety, negative general affects, and increased sleepiness and fatigue(p<.001). Dividing into high trait-anxiety group and low trait-anxiety group, there was significant sleep deprivation x traitanxiety interaction effect on general affect(p<.05). But, there was no significant sleep deprivation x trait-anxiety interaction effect on state-anxiety, sleepiness and fatigue. During sleep deprivation, the highest ratings of scales on anxiety, negative affect, sleepiness and fatigue occurred between 4 : 00AM and 7 : 00AM. Conclusions: These results show that sleep deprivation results in increased anxiety, mood state disturbance and increment of sleepiness and fatigue. These findings also suggest that trait-anxiety is a factor that influences the degree of worsening in general affect caused by sleep deprivation. During sleep deprivation, the rating curves of anxiety, affect, sleepiness and fatigue show rhythmicity that may be related to circadian rhythm.

• Journal of Nutrition and Health
• /
• v.52 no.1
• /
• pp.58-72
• /
• 2019

Purpose: This study examined the food and nutrient intake of Korean elderly according to the anxiety and depressive condition using the data from the Korea National Health and Nutrition Survey (KNHANES) from 2013 to 2015. Methods: The participants were 3,504 elderly people over 65 years of age (1,523 in men and, 1,981 in women). The dietary information was analyzed using the 24-hour recall data. The anxiety and depressive state was assessed using the self-reported scale EQ-5D in the quality of life dimension. The subjects were divided into the anxiety depression group (AD) and non-anxiety depression group (NAD) according to their anxiety and depressive conditions. Results: In the male elderly, the AD group had a significantly lower education and economic level and higher proportion in living alone than the NAD group. The percentage of eating lunch and dinner alone in the male AD group was higher than that of the NAD group. The female AD group showed less a lower frequency of dinner than the NAD group. The male AD group had a lower consumption of total foods, fish and shellfishes, seaweeds, mushrooms, oils and fats, and seasonings than the NAD group. With regard to the nutrient intake, the male elderly NAD group had more sufficient nutrient intakes than the AD group. In particular, the daily intakes of dietary fiber, riboflavin, niacin, potassium and iron were significantly lower in the AD group. To compare with the nutrient density of the two groups, the vitamin C and niacin intakes were lower in the AD group than in the NAD group. Overall, the nutritional status of the male AD group was significantly lower than that of the NAD group. Meanwhile, the female elderly had showed a smaller difference in nutrient intake according to their anxiety and depressive condition. Conclusion: These results of this study show that more nutritional education and emotional support are needed to improve the nutritional status and health of the male elderly with anxiety or depression.

• 대한불안의학회:학술대회논문집
• /
• 2005.05a
• /
• pp.14-24
• /
• 2005

o 기질적 행동억제(behavioral inhibition)은 조건 및 비조건 공포의 기저 기전의 신경계와 관련이 있다. o 환경적 영향이 행동 억제에 영향을 미친다. o인지과정이 행동 억제의 표현에 영향을 줄 수 있다. o 행동 억제는 정신병리의 위험 인자이다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.16 no.1
• /
• pp.124-131
• /
• 2005

Childhood and adolescent onset-bipolar disorders have higher rate of comorbidity with anxiety disorders as well as attention deficit hyperactivity disorder and conduct disorder. Obsessive compulsive disorder, social phobia, panic disorder, and separational anxiety disorder are common comorbid anxiety disorders with bipolar disorders in child and adolescent. Prospective and reliable data on temporal and causal relationship between the onset of bipolar disorders and the onset of comorbid anxiety disorders are still in debate. The authors report 2 adolescent cases with antidepressant induced-manic episodes with preceding anxiety symptoms. The authors suggest careful prescription of antidepressants for anxiety disorders, even for those who do not have definite past history or family history of bipolar disorders. Further comprehensive and prospective studies are requested for the temporal relationship and pharmacological guideline for comorbid bipolar disorders and anxiety disorder in child and adolescent.

• Korean Journal of Psychosomatic Medicine
• /
• v.11 no.1
• /
• pp.52-59
• /
• 2003

Objective: The purposes of this study were to investigate anxiety and depression that can mediate stress and elicit a response from the women with urinary incontinence and compare the anxiety and depression level before and after treatment of extracoporeal magnetic innervation. Method: Fifty-five women with urinary incontinence were included from a obstetrics and gynecology cilnic. Beck Anxiety Inventory(BAI), Beck Depression Inventory(BDI), Spielberger State-Trait Anxiety Inventory(STAI) were administered before and after treatment of extracoporeal magnetic innervation. Results: The women with urinary incontinence had higher levels of anxiety and depression. Anxiety and depression were reduced after treatment of extracoporeal magnetic innervation regardless of improvement incontinence. Conclusion: Therapies including extracoporeal magnetic innervation may be intrumental in improving anxiety and depression, If the patient do not show improvements of anxiety and depression after treatment for their urologic disorder or if the therapy is unsuccessful, appropriate referral is indicated.

• The Journal of the Korea Contents Association
• /
• v.16 no.11
• /
• pp.103-115
• /
• 2016

This study aims to examine the structural relationship between adverse childhood experience, anxiety, and internet addiction among youth probationers. The sample included 200 young probationers in Seoul probations office who were asked to fill out a self-administered survey questionnaire. Results from path analysis showed that adverse childhood experience positively influenced the risk for internet addiction (${\beta}=.396$, p<.05), and higher anxiety also predicted the internet addiction (${\beta}=.131$, p<.01). Mediating effect of anxiety between the adverse childhood experience and internet addiction was also confirmed. The study results indicated that prevention efforts for internet addiction is needed for this vulnerable population, and also implied the need to focus on dealing with childhood experience and anxiety in order to prevent problems related to internet addiction.

• The Journal of the Korea Contents Association
• /
• v.14 no.7
• /
• pp.324-333
• /
• 2014

This study was conducted to investigate the factors affecting the social anxiety in nursing students. A total of 227 nursing students participated in the study. Data were analyzed by frequencies, t-test, ANOVA, Pearson correlation coefficient, and multiple stepwise regression with SPSS WIN 18.0. The mean scores for problem solving ability and social anxiety were at the intermediate level. Problem solving ability negatively correlated with social anxiety. The significant predictors of social anxiety included cognitive reaction within the seven problem solving ability subscales and perceived interpersonal relationship. The regression model explained 22.6% of social anxiety. As a result, to decrease social anxiety in nursing students, nursing educators should develop educational intervention programs to change cognitive distortions presented in unfamiliar social situations and improve interpersonal relationships ability.

• Education of Primary School Mathematics
• /
• v.17 no.1
• /
• pp.41-56
• /
• 2014

The purpose of this study was to investigate how Storytelling in Mathematics Instruction effects students' mathematical communication apprehension. In order to do this, I selected two grade six classes with no significant difference on the Communication Apprehension(CA) test. I applied normal story telling and digital story telling to each of the classes for ten weeks then analyzed the effects through the post CA test. As a result, for Normal Storytelling Class (NSC), there was no meaningful difference in the ex ante and ex post CA test results. However, for Digital Storytelling Class (DSC), there was a meaningful difference in regards to the communication apprehension subgroup. Also, between the two NSC and DSC groups' post CA results, there was a meaningful difference in mathematics lesson and subgroup factors. Consequently, these results suggest the appliance of Digital Storytelling helps lower CA in $6^{th}$ graders participation in math class and subgroup.