• Journal of Nutrition and Health
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• v.34 no.1
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• pp.89-97
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• 2001

The relationship among food behavior, psychological factor(life strees) and perceive tiredness was investigated in 514 adolescents. Tiredness was measured in four cases: in lessons, before school, in the early evening and at weekends. Adolescents felt most tired in lessons and before school, and leat at weekends. Irregularity of meal times and skipping breakfast were positively correlated with tiredness in lessons and befor school. Consumption of some foods was related to perceived tiredness. High sugar or fat containing ice-cream, hamburger of fizzy drinks in boys, and crisps and cookies in girls were positively associated with tiredness. Whereas beans and mushrooms were negatively associated with tiredness in girls. Life stress(by scholastic problem and personal problem) of adolescents was positively related to tiredness. The contribution of stress to tiredness was much greater than of food behavior according to multiple linear regression .There was no relationship between nutrients intake and tiredness in lessons and before school which were more strongly influenced by stress, whereas the relationship was found at weekend without influences of stress. The more tired, the lower NARs(nutrient adequacy ratio) of energy, phosphorus, vitamin A, vitamin B$_2$, and niacin were. In conclusion, some eating behavior and psychological factor can cause tiredness in adolescents, but tiredness in school and before school had more of a psychological cause than at weekend. (Korean J Nutrition 34(1):89-97, 2001)

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.8 no.3
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• pp.7-12
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• 2012

Steam generator tubes are critical boundary of the primary and secondary side in nuclear power plants. Eddy current testing is commonly used as the method of non-destructive testing for the safety and integrity of steam generator tubes in the nuclear power plants. Changes in the geometric shape act as a stress concentration factor likely to cause a defect during the steam generator operation. The mixed-signals with the geometric shape are distorted and attributes that are difficult to detect signals. An example is bending stress due to compression process at a U-bend occurring in the intrados region which has a small radius of curvature. The resulting change in the geometric shape may lead to a dent like occurrences. The dent can cause stress concentration and generates stress corrosion cracks. In this study, the steam generator tubes of nuclear power plant were selected to study for analysis of mixed-signal containing dent and stress corrosion cracks.

• Proceedings of the Safety Management and Science Conference
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• 2012.04a
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• pp.35-41
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• 2012

The unsafe act and unsafe condition is induced by the fundamental cause factors of industrial accidents. In this paper, stress is classified into job, life and workplace stress. Therefore, the purpose of this paper is to develop a Korean stress model focused on the unmarried workers in order to prevent fundamental industrial accidents. The results of this paper are followed. First, the oriental culture and idea in Korea is directly connected to the central axis of all life. Accordingly, concrete and systematic safety management methods should be proposed from the point of Korean culture. Finally, the industrial accident questionnaire needs an item that reports the mental and physical condition of workers in order to prevent occupational diseases.

• Journal of Haehwa Medicine
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• v.8 no.2
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• pp.317-327
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• 2000

Through the study about Che-Qi-Jung(諸氣證) concerned with phenomenon of stress, we concluded as fallow. 1. Stressors are recognized three parts, internal cause, external cause, non-interexternal cause, in the oriental medicine. And the reaction of the body about stressors, was expressed change of Qi(氣). 2. The vascular system and autonomic nervous system are tensed or relexed. Because the etiology of Yuk-Em(六淫), Chil-Jeong(七情) make lose up and down, in and out, circulation of Gi(氣). The symtom caused with stress are explained, divided into Chil-Qi(七氣), Gu-Qi(九氣), Joong-Qi(中氣), Qi-Tong(氣痛), Qi-Yuk(氣逆), Qi-Wool(氣鬱). 3. The symtom of Chil-Qi is recognized into psycholoQical stress and Mae-Haek-Qi(梅核氣). The symtom of Gu-Qi is composed of Chil-Qi and Han(寒), Youl(熱), Ro(勞). 4. The symtoms of Qi-Yuk and Joong-Qi are caused by the ascent of Hwa-Qi(火氣). And Hwa-Qi is made by rage and depression. Qi-Yuk is chronic symtom that the ascent of Hwa-Qi is made by out of function in up and down mechanism of Qi. Joong-Qi is acute symtom that patholoQical state of Qi-Yuk take place for a while by sudden psycholoQical shock. 5. The symtom of Qi-Wool is loss of funtion made by depressed state in physioloQical mechanism, and Qi-Wool is observed in depressive psychosis and hypochondriasis and psychogenic. 6. The symtom of Qi-Tong is the pain caused by interference of circulation of Qi-Hyul(氣血). PsycholoQical stimulation such as rage and depression, tense autonomic nervous system. This make convulsion in gastro-intestine or vascular circuluation or abdominal muscles, and the pain is caused by convulsion.

• Magazine of the Korean Society of Agricultural Engineers
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• v.33 no.3
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• pp.51-62
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• 1991

A comprehensive laboratory investigation of the liquefaction characteristics of Jumunjin standard sand. Seoul sand and Hongsung sand was peformed by the undrained cyclic triaxial compression test under different relative densities, confining pressures and cyclic deviator stresses. The results obtained are as follows ; 1. Liquefaction potential was dominated by the stress ratio at a given number of cycle. That is, the number of cycle required to cause initial liquefaction became samller as the stress ratio increased. 2. Liquefaction potential of a sand was infliuenced by initial relative density or void ratio. Under a given relative density. liquefaction potential of Jumunjin standard sand and Seoul sand was smaller than that of Hongsung sand. 3. The pore pressure ratio of Hongsung sand was the smallest three under a given relative density and stress ratio, and it showed higher value when the cyclic stress and the shear strain were high. 4. An excessive pore pressure ratio not found when initial shear was smaller than 0.01%, and the pore pressure ratio started to increase when initial shear became greater than 0.01%. 5. Soil texture is an important factor to cause liquefaction, and liquefaction potential decreased a the mean grain size decreased. however the sand having fine grain such as Hongsung sand showed somewhat higher liquefaction potential. 6. Based on the analysis of the specimens whose number of the cycles to cause liquefaction was 8~12, it was found that the relationship between density and stress ratio was linear. The curves for Hongsung sand was steeper than the other. 7. From the above results and the method suggested by Seed-Idriss, it may be considered that the damages by Hongsung earthquake was not directly caused by liquefaction.

• YAKHAK HOEJI
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• v.52 no.3
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• pp.212-218
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• 2008

Manganese is a naturally occurring element which is widespread in the environment. Also, manganese is an essential trace element and plays a key role in important biological reactions catalyzed by enzymes. However, exposure to high levels of manganese can cause toxicity in neurone and inhalation system, also damage in various tissues. We investigated the toxicity induced by manganese compound ($MnCl_2$) in cultured rat cardiomyocytes. Treatment of manganese to cultured cardiomyocyte led to cell death, reactive oxygen species (ROS) increase, and cytosolic caspase-3 activation. The ROS increase was related with the decreased level of glutathione. Expressions of ROS related genes such as heme oxygenase-1, thioredoxin reductase, and NADH quinone oxidase were significantly induced in manganese treated cells. These results suggest that manganese induce oxidative stress and apoptosis in cardiomyocytes, and may be the one of risk factors to cause heart dysfunction in vivo.

• Anxiety and mood
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• v.13 no.1
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• pp.1-9
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• 2017

We reviewed the scientific literature on psychological effects of Chemical, Biological, Radiological, Nuclear, Explosive (CBRNE) disaster, which is one of the biggest threat to modern society. CBRNE disaster has the potential to cause specific physical symptoms and psychological distress in victims ; moreover, various toxic symptoms and carcinogenesis/mutation would be an important issue. Bioterrorism can cause localized outbreaks of infectious disease or pandemic disaster. Somatization as well as posttraumatic stress symptoms and depression are the characteristic psychological symptoms in CBRNE disaster's victims. CBRNE disasters could lead to large-scale public fear and social chaos due to the difficulties involved in verifying the extent of exposure and unfamiliar area to the common people. In the evacuation process, problems associated with adjustment and conflict between victims and residents should be considered.

• Journal of the Korean Society of Safety
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• v.12 no.3
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• pp.30-37
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• 1997

This paper deals with the residual stress of carburized spur gears is calculated being on the assumption that the main cause of residual stress is the volume difference between case and core due to the martensitic transformation in cooling. A formula is proposed to estimated the residual stress from the hardness and the amount of retained austenite. The estimated residual stress is close to the stress measured by X-ray method. The estimated residual stress is applied to the analysis of the fracture mechanics of carburized spur gear teeth. The stress intensity factor due to the residual stress is demonstrated. The stress intensity factor is computed by the influence function method, and it is shown that the factor is decreased by the residual stress in Carburized gear tooth.

• Corrosion Science and Technology
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• v.7 no.2
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• pp.77-84
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• 2008

Based upon the good compatibility to neutron irradiation and high temperature water environment, austenitic stainless steels are widely used for core internal structural materials of light water reactors. But, recently, intergranular cracking was detected in the stainless steels for the core applications in some commercial PWR plants. Authors studied on the root cause of the intergranular cracking and developed the countermeasure including the alternative materials for these core applications. The intergranular cracking in these core applications are defined as an irradiation assisted mechanical cracking and irradiation assisted stress corrosion cracking. In this paper, the root cause of the intergranular cracking and its countermeasure are summarized and discussed.

• Journal of the Korean Home Economics Association
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• v.41 no.6
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• pp.167-183
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• 2003

This study reviewed the literature pertaining to the cause and effects of job stress. Many definitions of stress have been offered and the diversity of these definitions has been generated by medical scientists, psychologists, and behavioral scientists. Most approaches dealing with job stress have involved listing of various sources of job stress, moderators, and outcomes. This study is concerned with the selection of variables, the relationships between job stressors and outcomes, and the effects of moderators on these relationships investigated in job stress research. A review of job stress literature presents that various job stressors (e. g., task characteristics, role characteristics, organizational characteristics, career development, and relationships), moderators (e. g., locus of control, type A and B personality, social support, and demographics), and outcomes (e. g., perceived stress, job satisfaction, job commitment, organizational commitment, performance, turnover, and physiological symptoms) were used for a greater understanding of job stress.