• Structural Engineering and Mechanics
• /
• 제78권2호
• /
• pp.135-143
• /
• 2021

In this study, continuous contact problem in the functionally graded (FG) layer loaded with a FG flat punch resting on the elastic semi-infinite plane was analyzed by the finite element method (FEM). It was assumed that the shear modulus and density of the layer and punch varied according to exponentially throughout their depth. FG layer's weight was included to the problem and additionally all surfaces were considered as frictionless. Analysis of FG materials was performed with a special macro which was added to the ANSYS program. Firstly, the shear modulus of the punch was considered to be very rigid and the results of initial separation load (λcr) and distance (xcr) were compared with the analytical solution. Afterwards, results obtained from the contact analysis made according to the inhomogeneity parameters (β, γ) between FG punch-FG layer which had been unprecedented in the literature were discussed. As a result, FG punch's stress values at the punch edges where stress accumulations occurred were found to be smaller than the rigid punch. The security of the structure, longer life of the material and ease of production are directly related to the reduction of the stress values. The results obtained in this study are important in this respect. Also this work is the first study that investigates the effect of FG punch on the FG layer.

• 디지털산업정보학회논문지
• /
• 제15권1호
• /
• pp.29-41
• /
• 2019

The purpose of this study examined how post-traumatic stress, caused when internet users in web portal or social media are defamed in cyberspace, influence on coping behaviour, through the Theory of Reasoned Action's two major factors: Attitude on behaviour and subjective norm. In so doing, it aims to provide a technical and political solution that would fundamentally prevent future victims in cyberspace. In an effort to examine its research theory, a survey was conducted on people who have had the experience of being defamed in cyberspace. The results showed, first, hypersensual has no significant influence over attitude on behaviour and subjective norm. Second, intrusion has no significant influence over attitude on behaviour and subjective norm. Third, avoidance showed significant influence over attitude on behaviour and subjective norm. Fourth, attitude on behaviour and subjective norm showed significant influence on behaviour. This study has both theoretical and practical significance; Unlike previous studies on cyber defamation with qualitative research method, this study employed quantitative method through theory-based approach. In other words, the researcher did not arbitrarily set variables, but utilized the Theory of Reasoned Action for examination.

• Steel and Composite Structures
• /
• 제47권3호
• /
• pp.355-363
• /
• 2023

The main purpose of this study is to characterize the size-dependent strain rate sensitivity in structural steel using the continue stiffness measurement (CSM) indentation. A series of experiments, such as CSM indentation and optical microscope examination, has been performed at the room temperature at different rate conditions. The results indicated that indentation hardness, strain rate, and flow stress showed size-dependent behavior. The dependency of indentation hardness, strain rate, and flow stress on the indentation size was attributed to the transition of the dislocation nucleation rate and the dislocation behaviors during the indentation process. Since both hardness and strain rate showed the size-dependent behavior, SRS tended to depend on the indentation depth. The results indicated that the SRS was quite high over 2.0 at the indentation depth of 240 nm and quickly dropping to 0.08, finally around 0.046 at large indents. The SRS values at large indentations strongly agree with the general range reported for several types of low-carbon steel in the literature (Chatfield and Rote 1974, Nguyen et al. 2018b, Luecke et al. 2005). The results from the present study can be used in both static and dynamic analyses of structures as well as to assess and understand the deformation mechanism and the stress-state of material underneath the indenter tip during the process of the indentation testing.

• 경영과정보연구
• /
• 제36권5호
• /
• pp.85-98
• /
• 2017

본 연구는 경북 북부지역 거주 직장인 332명을 대상으로 직무 의미감, Big 5 성격유형, 직무스트레스 간의 구조적 관계를 실증적으로 탐색한 것이다. 본 연구에서 밝혀진 주요한 사실은 다음과 같다. 첫째, 직무 의미감은 Big 5 성격유형의 친화성, 성실성, 외향성 요인에는 정(+)의 영향을 미치는 것으로 나타났다. 이는 개인이 수행하는 직무가 의미감이 커질수록 개인이 지닌 성격특성 중 친화성, 성실성, 외향성 등이 강화된다고 풀이할 수 있을 것이다. 둘째, 직무 의미감은 신경증 요인에는 부(-)의 영향을 미치는 것으로 드러났다. 이는 직무 의미감이 커지면 직무수행으로 인한 긴장, 화냄, 낙담 등이 줄어들 수 있다고 해석할 수 있다. 셋째, 직무 의미감은 성격특성 중 개방성 요인에는 통계적으로 의미 있는 영향을 미치지 않는 것으로 밝혀졌다. 넷째, Big 5 성격유형 중 신경증 요인은 심리적 스트레스와 신체적 스트레스에 정(+)의 영향을 미치는 것으로 드러났다. 이는 신경증 성향이 강한 사람일수록 스트레스에 취약하다고 풀이할 수 있다. 다섯째, Big 5 성격유형 중 개방성 요인은 심리적 스트레스와 신체적 스트레스에 부(-)의 영향을 미치는 것으로 드러났다. 이는 개방성향이 높은 사람들은 동일한 자극에도 개방성향이 낮은 사람에 비해 스트레스를 적게 경험할 수 있다는 것을 의미한다.

• 한국임상수의학회지
• /
• 제27권2호
• /
• pp.198-201
• /
• 2010

본 증례는 8개월령의 암컷 붉은목왈라비에서 발생한 포획근병증으로, 피부병 치료를 위하여 약욕 후 침울, 파행, 기립불능증의 임상증상을 보이다 14일 후에 폐사하였다. 왈라비가 기립불능 증상을 보인 다음날 실시한 혈액검사 에서, CK, ALT, AST의 상승을 확인하였다. 폐사 후 실시한 조직검사에서, 골격근과 심근의 근섬유가 퇴행되고, 괴사 된 소견을 발견할 수 있었다. 동거 개체로부터의 압박과 비타민 E의 부족이 의심되는 급여력, 약욕시의 스트레스등과혈액검사와 조직검사 결과 포획근병증으로 진단하였다. 포획근병증은 유대류에서 호발하는 질병으로 알려져 있으나 국내에서의 발병보고는 본 증례가 최초로, 포획근병증의 관리에 도움이 될 것이다.

• Journal of Oral Medicine and Pain
• /
• 제21권1호
• /
• pp.141-152
• /
• 1996

Oral Lichen Planus(OLP) is a idiopathic chronic inflammatory disease with more difficult to clear and higher recurrent rate than cutaneous lesions. But, there has been no estabilished theories about the proper treatment for OLP. The purpose of this study is to examine the clinical feature, relationship with systemic disease and dental treatment of OLP patients of Korea and to gain helpful information about clinical characteristics and treatment of OLP. The subjects chosen for the study were 54 patients who had visited Department of Oral Diagnosis & Oral Medicine at Yonsei University Dental Hospital Dental Hospital and diagnosed as OLP. Previous clinical records has been reviewed and questionnaires, oral examination, laboratory examination were done and recorded. The following results were obtained : 1. Of the 54 patients, 21 were men and 33 were women with an average age of 47.8 years. 2. The most common intraoral site was bilateral buccal mucosa, followed by unilateral buccal mucosa, gingiva, vesibule, lip mucosa, glossal mucosa, palatal mucosa and mouth floor. 3. The mixed, erosive and reticular form of OLP was most frequent(83.3%) clinical form. 4. OLP patients with liver disease were 5, and drug medication patients were 7. But, we could not find its evidence of association with OLP. 5. Associated events on onset of symptom were stress, denture wearing, dental treatemtn, and common cold. 6. Associated symptoms were dry mouth, tingling, sore throat, and altered taste perception. 30.8% of patients had no specific associated symptoms. 7. Aggravating factors of symptom were peppery food, hot food, fatigue, toothpaste, salty food, sour food, tension, and conversation. Reducing factors were cold food, sleeping. 69.2% of patients had no specific reducing factors. 8. There were no significant differences between normal papulation and OLP patients in CBC, SGOT< SGPT, Serum iron, Total iron binding capacity. 66.7% of subjects were positive response to fungus study for Candida Albicans. The incidence of stress and dental treatment on onset of symptom appeared high in OLP patients. Especially, high incidence of positive response to fungus study for Candida albicans, prescription of anti-fungal agents and dental treatment considerations may be helpful to treatment of OLP.

• 콘크리트학회논문집
• /
• 제28권1호
• /
• pp.23-31
• /
• 2016

수축 균열의 저감 대책으로서 팽창재를 적용한 콘크리트의 모델화에 관한 연구로서 선행하여 구축한 모델을 바탕으로 팽창재에 의한 콘크리트의 수축저감 및 균열억제 효과에 대한 매크로 예측 수법을 제안하고 타당성을 검증했다. 또한, 모델의 적용을 실부재로 확장해, 실부재에 발생하는 변형을 예측하는 한편, 실부재에 발생하는 응력을 예측하여, 기존의 방법에 따른 결과와 비교 검토함으로서 본 연구에서 제안하는 모델의 타당성을 검증했다. 본 연구로부터 실시한 팽창재를 혼입한 콘크리트에 대한 이론적인 모델의 검토로부터 팽창콘크리트의 실구조물 레벨로의 검토와 함께 수축저감 및 균열억제 효과에 대한 매크로 예측수법의 제안은 향후, 팽창콘크리트의 적용 및 실용화에 있어, 실증적인 데이터를 제공할 수 있다고 생각한다.

• 동의생리병리학회지
• /
• 제19권4호
• /
• pp.884-892
• /
• 2005

Seeing through the reference of literatures ${\ll}$Internal Classic${\gg}$, ${\ll}$Donguibogam${\gg}$ and Master Jisan's theory about Ki-Hyul and Hyul-Ki, the writer came to conclusions as follows. In ${\ll}$Internal Classic${\gg}$ Ki-Hyul is expressed into being orderly and ordinate, but Hyul-Ki is described differently into making Hyul-Ki or operating Hyul-Ki. In ${\ll}$Donguibogam${\gg}$ Ki-Hyul and Hyul-Ki are not distinguished between two things, but Ki-Hyul is mentioned as harmony of Ki-Hyul and Hyul-Ki, and Hyul-Ki as ascending and descending or as deficiency and excess. In Hyungsang medicine the special characters of Ki-Hyul is seized the essence of the meanings from the deflection between left and right, changes of skin, flesh, meridian, muscle and bones. And the distinctive marks of Hyul-Ki is got hold from changes of complexion, many or few hairs, ascending or descending spirits of ears, eyes, mouth and nose. Also Ki-Hyul is recognized by laying stress on rise and fall, after birth, breast, upper limbs, eight extra meridians. And Hyul-Ki is recognized by laying stress on going up and down, the inborn constitution, abdomen, lower limbs, and twelve meridians. Jisan distinguished Ki-Hyul from Hyul-Ki theoretically and he applied the theory to clinical examination proved the facts that the theory and the examination are in accord with each other. This attempts was for the first time in Oriental medicine history and the theory was set up. It is thought that the defects of the theory about Ki-Hyul and Hyul-Ki which Jisan insisted on need much more study from now on.

• 대한영양사협회학술지
• /
• 제24권4호
• /
• pp.344-360
• /
• 2018

This study examined the sociodemographic factors, health-related habits, chronic diseases, dietary habits, and nutrient intake according to the self-rated health status in a group aged over 65 years by analyzing the nationally representative Korean survey data. A total of 1,510 subjects were analyzed among the participants of the 2016 Korean National Health and Examination Survey (KNHANES). Statistical analyses for complex samples were performed using the SPSS software package (version 19.0) The study subjects were divided into two groups (healthy group vs. unhealthy group) based on their self-rated health status. The percentage of the healthy group was 66.5%. Gender, age, education level, household income, job (P<0.001, respectively), marital status, and basic living allowance (P<0.05, respectively) were significant sociodemographic variables of the self-rated health status. Alcohol consumption (P<0.01), aerobic physical activity, stress, quality of life, not feeling very well, depression and activity restriction (P<0.001, respectively) were also significant health-related variables of the self-rated health status. Blood glucose, anemia (P<0.05, respectively), and chewing problems (P<0.001) were significant chronic disease-related variables of the self-rated health status. Adequate intakes of protein, dietary fiber, phosphorus, thiamin, niacin, vitamin C (P<0.001, respectively), calcium, sodium, potassium (P<0.01, respectively), iron, vitamin A, and riboflavin (P<0.05, respectively) were also significant variables of the self-rated health status. In complex samples multiple logistic regression analysis, the self-rated health status was influenced significantly by the aerobic physical activity (P<0.01), stress level (P<0.05), depression (P<0.001), quality of life (P<0.001), not feeling very well (P<0.001), activity restriction (P<0.001), chewing problem (P<0.05), and adequate intake of iron (P<0.05). These results suggest that activity restriction, mental health, adequate iron intake, and physical activity may be associated with the self-rated health status in the elderly.

• 대한지역사회영양학회지
• /
• 제20권1호
• /
• pp.30-40
• /
• 2015

Objectives: This study was performed to investigate the associations of food security with socio-demographic characteristics, nutrient intakes and mental health status among older Korean adults. Methods: This study was conducted using data from the 2008-2010 Korea National Health and Nutrition Examination Survey (KNHANES). Subjects were 4,451 adults aged 65~98 years. Food security was measured using a self-reported question on food sufficiency of subjects' household. Based on the answers, study subjects were classified into secure, mildly insecure, moderately insecure, and severely insecure groups. Dietary intake was estimated by 24-hour dietary recall. Nutrient intake was assessed by dietary reference intakes (DRI). As for mental health status, the data on mental stress, depression, and suicide ideation were used. Results: Rate of food insecurity in older adults was 14.3%. Old age, being female, low education, low income level, living alone, and discomfort in daily living were more related to food insecurity. Means of nutrient intakes were significantly different according to food security status. Intakes of calcium, potassium, and vitamin $B_2$ were lower than recommended intakes in all groups. Consumption amounts of soy and soybean products, vegetables, mushrooms, fruits, vegetable oils, meats, eggs, seafood, and dairy products were lower in food insecure groups. Mental stress, depression, and suicide ideation were higher in food insecure groups independent of the gender and income level. Conclusions: These present findings suggested that food security is related to mental health as well as nutrition status in older Korean adults. A national system that include food and psychosocial support programs for the elderly should be considered in order to improve the overall health of older Korean adults.