• Journal of Korean society of Dental Hygiene
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• v.15 no.3
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• pp.389-397
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• 2015

Objectives: The purpose of the study is to examine the behaviors by the degree od dry mouth related to stress, dry mouth and halitosis. Methods: The subjects were 400 adults. A self-reported questionnaire was completed from August 1 to November 30, 2014. The data were analyzed using SPSS 18.0 program. The questionnaire consisted of eight questions of general characteristics of the subjects, one question of subjective stress symptom, six questions of dry mouth symptom, four questions of dry mouth behavior, and one question of halitosis. Results: There was a significant difference between halitosis and stress in patients having systemic diseases. Stress had a significant difference with gender, income, drinking frequency and alcohol consumption. The degree of dry mouth had a significant difference with gender and age. In dry mouth severity, behavior showed a significant difference with age, education, and times and amount of alcohol consumption. Age had a positive correlation with cigarette consumption and a negative correlation with dry mouth and dry mouth behavior. Cigarette consumption showed a positive correlation with alcohol consumption. Drinking frequency had a positive correlation with alcohol consumption, dry mouth, dry mouth behavior, halitosis and stress. Alcohol consumption had a positive correlation with dry mouth behavior, and dry mouth showed a positive correlation with dry mouth behavior, halitosis and stress. Dry mouth behavior had a positive correlation with halitosis and stress, while halitosis showed a positive correlation with stress. Conclusions: Stress, dry mouth and halitosis were closely correlated. Since stress is the most important variable, stress relief will be the most effective measure to alleviate oral symptoms. Therefore, stress relief measures need to be devised for oral health management in adults having stressful life.

• Journal of Korean society of Dental Hygiene
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• v.13 no.4
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• pp.589-596
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• 2013

Objectives : The aim of the study is to investigate the influence of the stress of adults on their oral mucosal diseases, dry mouth and physical, mental stress symptoms. Structured equation model (SEM) was used to analyze the hypotheses of the study. Methods : The subjects were 500 adultsfrom July 1 to December 31, 2012. The data were analyzed using SPSS 18.0 (SPSS 18.0 K for window, SPSS Inc USA) and IBM SPSS Amos 18.0 (SPSS Inc, Chicago, IL, USA) set at the level of significance as 0.05. Results : The level of stress had a direct influence on oral mucosal diseases, and oral mucosal diseases affected stress symptoms directly. The level of stress had a significant impact on stress symptoms, and that exercised an indirect influence on stress symptoms through the medium of oral mucosal diseases and dry mouth. The level of stress affected dry mouth in a direct effects, and dry mouth had a direct impact on stress symptoms. Conclusions : The stress of adults had direct and indirect impacts on their oral health and systemic diseases. The oral health of adults should be promoted to let them stay healthy, and how to help them to get rid of their stress should be considered to improve their quality of life.

• Journal of Korean society of Dental Hygiene
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• v.13 no.1
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• pp.136-145
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• 2013

Objectives : The goal of this study is to investigate how occupational stress affects temporomandibular disorders (TMD), dry mouth and oral symptoms. Methods : For this study, workers from 5 areas were selected and the survey was carried out from June 1st to 30th, 2012. A total of 410 questionnaires were analyzed. Results : The analysis of the structural model shows that occupational stress has no significant influence on temporomandibular disorder and dry mouth symptoms, but does affect other oral symptoms. The results also reveal that dry mouth symptom and temporomandibular disorder both have a significant effect on oral symptoms. Conclusions : Oral symptoms and job stress appeared to directly and indirectly influence the psychological and social factors of job stress. A systemic investigation on the improvement of oral health in workers is urgently required.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.197-208
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• 2023

The objective of this study was to investigate the effects of a traditional dry period (60 d) versus a no dry period (0 d) on the milk production, physiological response, and metabolic status of dairy cows exposed to heat stress during the transition period. Holstein dairy cows (n = 15) with similar expected calving dates were randomly assigned to two different dry period lengths: (1) no dry period (n = 7) and (2) a traditional dry period of 60 days (n = 8). All cows were studied from 8 weeks before expected calving to 10 weeks after calving and experienced heat stress during the transition period. The results showed that cows with no dry period decreased their milk yield in subsequent lactation, but compensated for the loss of milk yield accounted for by additional milk yield before calving. The energy balance at postpartum was improved in cows with no dry period compared to cows with a traditional dry period. There were no significant differences in the physiological response and blood metabolites at postpartum between the dry period lengths of dairy cows exposed to heat stress during the transition period. Taken together, our results showed that omitting the dry period improved the milk production and metabolic status of dairy cows exposed to heat stress during the transition period.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.205-214
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• 2021

Currently, the interim storage pools of spent fuels in South Korea are expected to become saturated from 2024. It is required to prepare an operation plan of a domestic dry storage facility during a long-term period, with the researches on safety evaluation methods. This study modified the FRAPCON code to predict the spent fuel integrity evaluation such as the axial cladding temperature, the hoop stress and hydrogen distribution in dry storage. The cladding temperature in dry storage was calculated using the COBRA-SFS code with the burnup information which was calculated using the FRAPCON code. The hoop stress was calculated using the ideal gas equation with spent fuel information such as rod internal pressure. Numerical analysis method was used to calculate the degree of hydrogen diffusion according to the hydrogen concentration and temperature distribution during a dry storage period. Before 50 years of dry storage, the cladding temperature and hoop stress decreased rapidly. However, after 50 years, they decreased gradually and the cladding temperature was below 400 K. The initial temperature distribution and hydrogen concentration showed a parabolic line, but hydrogen was transferred by the hydrogen concentration and temperature gradient over time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.190-195
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• 2013

In this study, the response of 22 soybean cultivar sprouts to flooding stress was investigated. After sprouts were subjected to flooding stress for 10 days at the V4-V5 growth stages, their dry weights were compared. All plants were kept in a greenhouse under natural light conditions, an average daytime temperature of $35.6{\pm}5.3^{\circ}C$ and an average nighttime temperature of $18.2{\pm}1.7^{\circ}C$. Soybeans were grown in a concrete bed filled with silt loam soil. Subjecting plants to flooding stress resulted in a large reduction in plant dry weight, plant height, number of nodes, and number of leaves. Cultivars differed significantly in their responses to flooding stress, as indicated by these characteristics (p<0.05). Soybean cultivars were classified into three groups based on their degree of flood tolerance: strong, moderate, and weak. Hannamkong, Namhaekong, Sobaegnamulkong, and Sorogkong had strong tolerance for flood conditions. Tawonkong, Pureunkong, Eunhakong, Myeongjunamulkong, Doremikong, Saebyeolkong, Paldokong, Sowonkong, Pungsannamulkong, Dagikong, Dachaekong, and Anpyeongkong had weak tolerance for flood conditions.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1486-1494
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• 2020

To evaluate transport-induced cladding embrittlement after interim-dry storage, ring compression tests were carried out at room temperature(RT) and 135 ℃. The ring compression test specimens were prepared by simulating the interim-dry storage conditions that include four peak cladding temperatures of 250, 300, 350 and 400 ℃, two tensile hoop stresses of 80 and 100 MPa, two hydrogen contents of 250 and 500 wt.ppm-H and a cooling rate of 0.3 ℃/min. Radial hydride fractions of the ring specimens vary depending on those interim-dry storage conditions. The RT compression tests generated lower offset strains than the 135 ℃ ones. In addition, the RT and 135 ℃ compression tests indicate that a higher peak cladding temperature, a higher tensile hoop stress and the lower hydrogen content generated a lower offset strain. Based on the embrittlement criterion of 2.0% offset strain, an allowable peak temperature during the interim-dry storage may be proposed to be less than 350 ℃ under the tensile hoop stress of 80 MPa at the terminal cool-down temperature of 135 ℃.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.792-797
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• 2009

The stress-strain characteristics of compacted bentonite are investigated using experimental triaxial compression test by Hoek-cell. Special attention given to various dry density and water absorption ratio. Based on the test results, it is shown that the stress-strain relationship of compacted bentonite is highly influenced by dry density and water absorption ratio. Also, characteristics of Bentonite is similar to the clay rather than sand. Strength of compressed Bentonite increases with higher dry density. It shows maximum strength value, if in a same condition with dry density and constrain pressure. So we determine that value as the optimistic moisture contents for the maximun strength of compressed Bentonite.

• Journal of Oral Medicine and Pain
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• v.41 no.3
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• pp.99-109
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• 2016

Purpose: This study investigated factors influencing the xerostomia symptoms in the patients with temporomandibular disorders (TMDs). Methods: Eighty-six participants over the age of twenty were randomly enrolled from patients with TMDs. The patients were diagnosed by Diagnostic Criteria-TMD (DC-TMD). Intensity of the pain and level of stress of the patients were recorded using TMD pain visual analogue scale (VAS) and stress VAS, respectively. The Symptom Checklist-90-Revised (SCL-90R), dry mouth symptom questionnaire, unstimulated salivary flow rate (USFR) and oral moisture were measured. Results: The patients who had above the mean of the TMD pain VAS had significantly higher scores on the stress VAS, subjective dry mouth symptoms and T-score of somatization. The patients who suffered from pain more than three months had significantly higher TMD pain VAS, subjective dry mouth symptoms and T-score of somatization. There were no significant differences in xerostomic symptoms according to the diagnosis of TMDs. Moreover, TMD pain VAS and the stress VAS did not correlated to USFR and oral moisture. Conclusions: The level of individuals' TMD pain and stress significantly affect their subjective dry mouth symptoms, however, it did not affect USFR and oral moisture.

• Journal of Navigation and Port Research
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• v.29 no.3 s.99
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• pp.263-268
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• 2005

Laboratory evaluation of the effect of fines, confine stress and dry density on the permeability characteristics in sand columns is presented. The triaxial permeability tests were conducted on different contents of fines(5, 15, 25, $35{\%}$), confine stress ($\sigma_3^'=0.5,\;1.0,\;2.0,\;3.0{\cal}kg/{\cal}cm^2$), and dry density($\gamma_d=1.50,\;1.55,\;1.60,\;1.65{\cal}g{\cal}cm^3$). The results of triaxial permeability tests showed that as the contents of fines, confine stress and dry density became increase permeability became decrease. For the contents of fines, when the fines that smaller than $0.01{\cal}mm$ increases the permeability decreases significantly. For the confine stress and the dry density, the permeability is decreased significantly at changes of the confine stress($\sigma_3^'=0.5{\~}1.0{\cal}kg/{\cal}cm^2$) and the dry density($\gamma_d=1.50{\~}1.55{\cal}g/{\cal}cm^3$) at lower levels.