• The Journal of Engineering Geology
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• v.27 no.1
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• pp.51-58
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• 2017

The purpose of this study was to quantitatively evaluate the state of rocks in load steps by using the low-frequency ultrasonic flaw detection method. The initial Vp-velocities measured with a CND tester were in the order of Z-axis < X-axis < Y-axis, with 1687.5 m/s along the X-axis, 1690.7 m/s along the Y-axis, 1548.3 m/s along the Z-axis, and an average of 1642.2 m/s. The overall average of the Q vlaues, measured with a Silver Schmidt hammer, was 62.6, which corresponds to a uniaxial compressive strength of ~105 MPa. The Vp-velocity, measured with a low-frequency ultrasonic flaw detector at load steps of 50%, 60%, 70%, and 80%, typically decreases in the order of X-axis < Y-axis < Z-axis with increasing load steps. This oder contrasts with that of the initial Vp-velocities. As the load step increases the factors that reduce the Vp-velocity in the X-axis direction are more influential than those in the Y-axis or Z-axis directions. This indicates that the initial state of rocks can vary and is dependent on the stress state.

• Journal of Life Science
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• v.9 no.2
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• pp.169-175
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• 1999

Salmonella typhimurium can encounter a wide variety of environments during its life cycle. In nature, S. typhimurium can experience and survive dramatic acid stresses that occur in diverse ecological niches ranging from pond water to phagolysosomes. These survival mechanism is aquired by the Acid Tolerance Response(ATR) in Salmonella. The ATR of S. typhimurium is a complex inducible phenomenon in which exposures to slight or moderate low pH will produce a stress response capable of protecting the organism against more severe acid challenges. ATR in Salmonella has two different systems that are called RpoS dependent and independent. We found that ATR in anaerobic was showed RpoS independent because rpoS$\Omega$AP had ATR as S. typhimurium UK1. Using the P22 MudJ(Km, lacZ) operon fusion technique and a lethal selection procedure combining low pH(pH4.5) and sodium acetate(10mM, pH4.5), we isolated LF487 aatA::MudJ which showed acid sensitive in anaerobic condition. aatA locus was determined at 12 min on Salmonella Genetic Map. The survival rate of aatA mutant was showed significantly diminished at pH4.3 than virulent wild type Salmonella in anaerobic condition(5% $CO_2$, 5% H$_2$, 90% $N_2$). Therefore isolated gene was confirmed important gene for anaerobic ATR system.

• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.568-573
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• 2004

Effects of dry heating and pH on pasting, thermal, and textural properties of corn starch containing soy protein isolate (SPI) were investigated. Samples were prepared by drying corn starch dispersions containing 3% SPI at $40^{\circ}C$ (unheated sample) or additionally heating dried mixtures at $130^{\circ}C$ (heated sample). Pasting properties of starch samples and textural properties of starch gels were measured using Rapid Visco-Analyzer (RVA) and Texture Analyzer (TA), respectively. Effects of SPI addition and dry heating on retrogradation and microstructure of gel samples were investigated using DSC and SEM, respectively. Pasting viscosity of dry-heated samples was significantly higher than that of unheated samples, and at pH 8 compared to pH 6. Dry-heat treatment decreased fracture stress and strain of starch gels containing SPI. No significant effects of dry-heat treatment and pH were observed on retrogradation of starch gels. Addition of SPI retarded starch retrogradation and modified starch gel properties with increased nutritional value. Dry-heat treatment with SPI could be possible method for starch modification.

• Korean Journal of Biological Psychiatry
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• v.12 no.2
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• pp.136-142
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• 2005

Object:The intracellular action of the antidepressant, venlafaxine, was studied in C6-gliomas using heat shock protein 70(HSP70) immunocytochemistry and HSP70 Western blots because HSP70 is associated with stress and depression. Methods:To examine how the glucocorticoid affects the expression of HSP70 in nerve cells, the rat C6 glioma cell was treated with dexamethasone for 6 hours. In addition, venlafaxine was administered to the experimental groups of C6 glioma cells for 1, 6, 24, and 72 hours each, after which the expression of HSP70 was investigated. Finally, venlafaxine and dexamethasone were simultaneously administered to the experimental groups for 1, 6, 24, and 72 hours, followed by an investigation of the expression of HSP70. Results:The short term(1 hour) venlafaxine treatment significantly increased the level of HSP70 expression. The short term treatment of venlafaxine with dexamethasone also increased the level of HSP70 expression but this reduction was not statistically significant. The long term(72 hours) venlafaxine with dexamethasone treatment significantly reduced the level of HSP70 expression. The long term treatment of venlafaxine also reduced the level of HSP70 expression but this reduction was not statistically significant. Dexamethasone(10uM, 6hours) did not affect the level of HSP70 expression compared with controls. Conclusion:Venlafaxine increases the expression of HSP70 at short term treatment, but prolonged treatment with dexamethasone suppresses the expression of HSP70.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.256-267
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• 2010

Earthquakes in the Korean Peninsula occur along the faults formed and boundaries between major geological units ruptured due to violent tectonic activities during the Mesozoic. E-W and/or ENE-SSW compressive stress regime resulting from collisions between the Eurasian plate and neighbouring the Indian plate, the Pacific plate and the Philippine plate trigger Korean earthquakes of thrust faulting with predominant strike-slip components along the mostly NNE-SSW trending active faults. Seismicity of the Korean peninsula has been moderate to low during the past 20 centuries except for the period from the 15th to the 18th centuries of exceptionally high seismicity, showing the typical irregularity of intraplate seismicity. The structure of the Korean peninsula is rather homogeneous without the Conrad discontinuity sharply dividing the upper and lower crust. Lateral heterogeneities exist in the crust. The crust with an average thickness of about 33 km is thicker in the mountainous region than the plain due to the Airy-type isostatic equilibrium maintained in the peninsula. Crustal P-wave velocity with average of about 6.3 km/sec increases gradually from the near surface to the Moho. The upper mantle P-wave (Pn) velocity is about 7.8 km/sec.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.407-414
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• 2010

The fairway within the area of Yul-do and Songdo located near the Myeongnyang-sudo approaches south of Mokpo harbor is well guided by traffic separation scheme and other navigational aids. However, that part of the waterways where Yul-do is located sits at the cross-roads of marine traffic and is subjected to some potential risks in the voyage navigation: the effect of climatic phenomenon, the disregard of most ships in using the western sector of the fairway creating a congestion in the eastern sector, and lastly, the disadvantageous erect of the location and height of Yul-do island that hinders good lookout. This study investigates the environmental conditions that prevailed in the area in the span of 5-year period and the marine traffic situation taken from the data within the 72-hour period The navigational hazards and marine casualties are also be presented. The results are analyzed and are made the basis of a proposal for an improved separation of traffic. Thereafter, an evaluation is carried out by using the components of marine traffic flow simulation and ES modeling index. It is evaluated through simulation by the use of full-mission ship handling simulator.

• The Journal of Korean Physical Therapy
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• v.17 no.2
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• pp.22-37
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• 2005

This study was performed to investigate LBP(low-back pain) prevalence rate and its related factors inphysical therapists. A self-administered questionnaire survey was conducted to 522 physical therapists in Daegu and Gyeongsangbuk. The LBP prevalence rate for recent 6 months was $61.7\%$. According to age, the prevalence rate was highest in the group aged 24 or less for both male and female physical therapistis. For male physical therapists , it was higher in smokers and drivers, but for female ones, it was not in a significant relationship with smoking and driving. According to work experience, the prevalence rates of those who had been working for less than one year were the highest, and those who had been working at hospitals and clinics were $69.1\%$, significantly high. According to therapy techinque, the prevalence rate related ti PNF was $71.6\%$, the highest and to occupational therapy was $34.3\%$, the lowest. According to working environment for six months, in both male and female physical therapists. LBP prevalence rate was in a statistically significant relationship with work hours during the day, night and weekend duties, repetitive works, motions that bend or twist the waist, the number of patients per day, the number of time to help patients per day, the number of time to carry medical equipment per day and the length of time to work standing. The rate was also higher when physical therapists fekt nire stress from their work. According to the result of multiple logistic regression analysis, male was in a significant relationship with work experience and motions that bend or twist the waist and female was in a significant relationship with work hours during the night and weekend duties, the number of time to help patients per day, motions that bena or twist the waist, actions taken to protect the waist. As for the developmental pattem of LBP in the group of physical therapists with LBP for six moths, $15.7\%$ of them had LBP for first time, $42.3\%$ had recurred LBP, and $42.0\%$ had chronic LBP. As for the causes of LBP, $51.7\%$ said that it was because they worked in the same posture for a long time, and as for how to treat LBP, 48.8% said that they treated themselvs or got help from their co-wokers. The results presented above suggest that physical therapists are exposed to high risk of LBP caused form occupational activities. Therefire, it is necessary to improve working environment to reduce the occurrence of LBP and to develop education programs for preventing the occurrence and recurrence of LBP.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.446-457
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• 2019

The purpose of this study was to analyze the association between family members and adolescent boys smoking. The data were evaluated by frequency analysis, 𝑥² test and logistic regression analysis using 27,276 people who responded to the 14th(2018) Korean Youth Risk Behavior Survey. Among male students, the nonsmoking rate was 91.5% and the smoking rate was 8.5%(2.5% of occasional smoking and 6.0% of frequent smoking). The study results showed that the smoking status of male students was varied significantly according to the number of smokers among the family members(p<0.001). Meanwhile, smoking based on the characteristics of socio-demographic factors was affected by grades, school records, economic status, and parents' educational background(p<0.001). Smoking by health factors showed a significant difference in alcohol consumption, suicidal thoughts, depression experiences, stress recognition, frequency of breakfast consumption, level of fatigue after sleep, and subjective perception of health(p<0.001). Male smokers were more likely to smoke when two family members smoked than only one(p<0.001). These results confirmed that smoking in boys was affected by the smoking status of family members and suggested that the smoking cessation program of family smokers can be effective in designing smoking cessation prevention and smoking cessation projects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.455-464
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• 2020

This study examined the correlation between the variables related to the organizational commitment of social workers. The research results are as follows. First, the overall effect size of the variable group had an intermediate effect size. Among the four organizational commitment-related variables, the job-related negative variable had the largest effect size. Next, the group of positive variables related to the organization, the group of positive variables related to the job, and the group of individuals related to the individual were in order. Second, among the individual-related variables, experience, gender, and education showed a small effect size, and other factors were close to the small effect size. In the group of positive variables related to organization, all variables except for transactional leadership and organizational fairness, which had a medium effect size, showed a large effect size. The job-related positive variables showed a large effect size only for job satisfaction, and customer orientation and job suitability were close to the large effect size. The turnover intention, which is a group of job-related negative variables, had a large effect size and job stress showed a medium effect size.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.5
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• pp.111-118
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• 2011

With increasing interest in health promotion and quality of life, growing attention has been focused on the beneficial effects of urban green area. However, very few evidence-based approaches have been conducted on the health-related benefits of urban greenery. Therefore, this study examined the health-related benefits of green areas using physiological and psychological indices to obtain evidence-based data on these benefits. Twenty male university students were selected as subjects. Data were collected when participants viewed landscapes in a green area or an urban area for fifteen minutes. This research was reviewed and approved by the Ethics Committee of School of Medicine, Chungnam National University. Physiological data in the green area revealed significantly decreased heart rates, significantly increased high-frequency value of heart rate variability, an index of parasympathetic activity, and reduced salivary cortisol concentration, a stress hormone, compared to the urban area. Psychological tests showed the green area significantly reduced the negative mood state and psychological symptoms, and significantly increased the positive mood state. Our data provided evidence for the health-related benefits of green areas, and the findings of this study support that green areas can play a critical role in health promotion for urban residents, by positively affecting autonomic nervous and endocrinal activities.