• Journal of the Korean Society of Safety
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• v.8 no.4
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• pp.27-40
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• 1993

High temperature tensile tests, steady state creep tests, Internal stress tests and creep rupture tests using A17075 alloy( $T_{6}$ ) were performed over the temperature range of 9$0^{\circ}C$~50$0^{\circ}C$ (0.4 $T_{m}$ ~0.85 $T_{m}$ ) and stress range of 0.64~17.2(kgf/$\textrm{mm}^2$). The main results obtained in this paper were as follows. (1) The activation energies for yielding at the temperature of 0.4 $T_{m}$ ~0.75 $T_{m}$ were calculated to be 25.7~36.5kcal/mol, which were nearly equal to the activation energies for creep. (2) At around the temperature of 9$0^{\circ}C$~12$0^{\circ}C$ and under the stress level of 10~17.2(kgf/$\textrm{mm}^2$), and at around the temperature of 200~41$0^{\circ}C$ and under the stress level of 1.53~9.55(kgf/$\textrm{mm}^2$) and again at around the temperature of 470~50$0^{\circ}C$ and under the stress level of 0.62~l.02(kgf/$\textrm{mm}^2$), the applied stress dependence of steady state creep rate $n_{measu}$ measured were, respectively, 3.15, 6.62 and 1.1, which were in good agreement the calculated stress dependence $n_{ealeu}$ obtained by the difference of the applied stress dependence of the Internal stress and the ratio of the internal stress to the applied stress. (3) At the temperature range of 0.4~0.43 $T_{m}$ , and at the temperature range of 0.52~0.75 $T_{m}$ and again at the temperature range of 0.82~0.85 $T_{m}$ , the activation energies $Q_{measu}$ obtained by steady state creep rate, respective, 26. 16, 34.9, 36.2 and 36.1kcal/mol, which were in good agreement with those obtained with the activation energies under constant effective stress and the temperature dependence of Internal stress. (4) At the temperature range of the 0.52~0.73 $T_{m}$ and under the stress level of 1.53~9.55(kgf/$\textrm{mm}^2$), the stress dependence of rupture life(n’) measured was 6.3~6.6, which was in good agreement with the stress dependence of steady state creep rate(n). And at the same condition the activation energy for rupture( $Q_{f}$ ) measured was 32.0~36.9kca1/mol, which was also in good agreement with the activation energy obtained by steady state creep rate ( $Q_{c}$ ). (5) The rupture life( $t_{f}$ ) might be represented by athermal process attributed to the difference of the applied stress dependence of the internal stress and the ratio of the internal stress to the applied stress, and the thermal activated process attributied to the temperature dependence of the internal stress as $t_{f}$ = A'$\sigma$$_{a}$ ｛n(1-d $\sigma$$_{i}$ /d $\sigma$$_{a}$ )/(1-$\sigma$$_{i}$ / $\sigma$$_{a}$ )｝.exp[｛ $Q_{c}$ $^{*}$-( $n_{o}$ R $T^2$/ $E_{(T)}$) (d $E_{(T)}$/dT) - ( $n_{0}$ R $T^2$/ $\sigma$$_{a}$ - $\sigma$$_{i}$ ) (d $\sigma$$_{i}$ /dT)｝/RT]. (6) The relationship betwween Larson-Miller rupture parameter and logarithmic stress was linearly decreased, so creep rupture life of Al 7075 alloy seemed to be predicted exactly with Larson-Miller parameter.meter.

• The Korean Society of Law and Medicine
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• v.9 no.2
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• pp.231-267
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• 2008

Tobacco has become the world's leading cause of deaths and diseases. And !be tobacco use and dependence itself is a kind of diseases, so-called "mental and be-havioural disorders due to use of tobacco" in "International Statistical Classification of Diseases and Related Health Problems(ICD-10)" and "Korean Standard Classification of Diseases". The tobacco use and dependence is a chronic disease that requires repeated clinical interventions and multiple attempts to quit. But effective treatments to the tobacco use and dependence are developed and exist that can significantly increase the rate of long-tenn smoking abstinence. So the physicians should warn smoking patients about the dangers of smoking to the health and the life, and the clinicians ought to provide one of more of the treatments which have been proven effective in helping smokers quit to smoke. It has been concluded that if a doctor failed to provide effective treatment for smokers, and the smokers subsequently died of the smokers-related conditions(tobaccosis) or became incapacitated by the tobaccosis the smokers were considered in the medical malpractice. Thus the smokers could sue the physician for medical malpractice, claiming that the doctor's legal responsibility of appropriate treatments including smoking-cessation which the physician deliberately or negligently breached.

• International journal of advanced smart convergence
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• v.7 no.2
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• pp.127-134
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• 2018

This study found the digital divide of Korean elderly persons on the basis of the 2013-2017 survey data of the perception of media information adopters. The studied media were traditional ones, such as newspaper and TV. The media dependence of those in their 20s to 60s was compared and analyzed. As a result, regarding their dependence on newspaper, elderly persons in their 60s had 20.7% on average, 13.6% higher than the percentage (7.1%) of young persons. Regarding their dependence on TV, those in their 60s had 97.6% and those in their 20s had 63.7%, so that there was a wide gap of 33.9% on average. The smartphone penetration rate of those in their 60s was 61.3%(2015-2017) on average, which tended to rise. The elderly's dependence on traditional media featured Digital Divide which is found in the informatization process. Accordingly, in order to solve their digital divide, it is required to expand education in line with their knowledge level through remote online centers, develop inclusive ICT for convenience, and change philosophical policy paradigm in the dimension of quality of life.

• 한국초전도학회:학술대회논문집
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• v.14
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• pp.18-18
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• 2004

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.579-582
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• 2013

Background: In this study our aim was to determine the rate of smoking in a sample of psychiatric in-patients with diagnoses of schizophrenia, bipolar disorder and major depression and to examine factors related to smoking status and the level of dependence in this population. Materials and Methods: A total of 160 people were included in this descriptive study. 80 were inpatients with schizophrenia, bipolar disorder and major depression and 80 people without any psychiatric diagnoses were included as a control group. The participants were interviewed face-to face using a semi-structured questionnaire and Fagerstrom Test for Nicotine Dependence was used to define smoking habits. Results: The mean age of the participants was $37.24{\pm}12.19$ years ranging from 18 to 81 years, 54.4% of the participants were (n=87) female, and 45.6% cases (n=73) were male. 70% (n=56) of the patients and 55% of the control group were smoking and the difference was statistically significant (p<0.01). Total score of Fagerstrom Test for Nicotine Dependence in the patient group was statistically significantly higher than in the control group (p<0.01). Conclusions: In our sample, the frequency of cigarette smoking and nicotine dependence among psychiatric inpatients was high, posing a high risk for smoking related diseases including cancers; therefore there should be counseling on tobacco control and smoking cessation programming targeting this population.

• Korean Journal of Materials Research
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• v.24 no.11
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• pp.625-631
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• 2014

To investigate the deformation properties of TiC-(5-20) mol% Mo solid solution single crystals at high temperature by compression testing, single crystals of various compositions were grown by the radio frequency floating zone technique and were deformed by compression at temperature from 1250K to 2270K at strain rates from $5.1{\times}10^{-5}$ to $5.9{\times}10^{-3}/s$. The plastic flow property of solid solution single crystals was found to be clearly different among a three-temperature range (low, intermediate and high temperature ranges) whose boundaries were dependent on the strain rate. From the observed property, we conclude that the deformation in the low temperature range is controlled by the Peierls mechanism, in the intermediate temperature range by the dynamic strain aging and in the high temperature range by the solute atmosphere dragging mechanism. The work softening tends to become less evident with an increasing experimental temperature and with a decreasing strain rate. The temperature and strain rate dependence of the critical resolved shear stress is the strongest in the high temperature range. The curves are divided into three parts with different slopes by a transition temperature. The critical resolved shear stress (${\tau}_{0.2}$) at the high temperature range showed that Mo content dependence of ${\tau}_{0.2}$ with temperature and the dependence is very marked at lower temperature. In the higher temperature range, ${\tau}_{0.2}$ increases monotonously with an increasing Mo content.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.80.2-81
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• 2016

We investigate the dependence of solar proton events (SPEs) on solar and interplanetary type II bursts associated with solar flares and/or CME-driven shocks. For this we consider NOAA solar proton events from 1997 to 2012 and their associated flare, CME, and type II radio burst data with the following subgroups: metric, decameter-hectometric (DH), and meter-to-kilometric (m-to-km) type II bursts. The primary findings of this study are as follows. First, about half (52%) of the m-to-km type II bursts are associated with SPEs and its occurrence rate is higher than those of DH type II bursts (45%) and metric type II bursts (19%). Second, the SPE occurrence rate strongly depends on flare strength and source longitude, especially for X-class flare associated ones; it is the highest in the central region for metric (46%), DH (54%), and m-to-km (75%) subgroups. Third, the SPE occurrence rate is also dependent on CME linear speed and angular width. The highest rates are found in the m-to-km subgroup associated with CME speed 1500 kms-1: partial halo CME (67%) and halo CME (55%). Fourth, in the relationships between SPE peak fluxes and solar eruption parameters (CME linear speed, flare flux, and longitude), SPE peak flux is mostly dependent on SPE peak flux for all three type II bursts (metric, DH, m-to-km). It is noted that the dependence of SPE peak flux on flare peak flux decreases from metric to m-to-km type II burst.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.2
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• pp.117-120
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• 2002

The effect of cell density on cell growth was investigated in a suspension batch culture of hybridoma cells. The specific growth rate was found to increase with increasing initial cell density and then to decrease with further increases in initial cell density. In order to quantitatively describe the dependence of specific growth rate on cell density, a kinetic model is proposed, which satisfactorily represents the experimental data.

• Journal of Convergence for Information Technology
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• v.9 no.9
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• pp.133-140
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• 2019

Following the recent US trade deficit, the trade war began between Korea and Japan in July. Korea's trade dependence is about 60% or more, indicating high export dependence and import dependence. The purpose of this study is to examine export amount, export volume, export price index, Treasury bond interest rate and analyze how index affects export amount. This study attempts to analyze the comovement and volatility with export amount. For this purpose, monthly data for each indicator were selected for a total of 234 months from January 2000 to June 2019. As a result of analysis, exports amount and exports volume showed very high comovement, exports amount and interest rates showed low comovement, but exports amount and exports prices showed very low comovement. In the future, Korea should continue to increase exports amount in view of its high dependence on trade, along with policies to expand the domestic market. To this end, strategy to increase exports volume should be presented. Korea should increase the logistics environment and competitiveness of each port and airport, improve domestic and overseas network construction and support services of logistics companies.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.773-777
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• 2006

Growth of Bacillus cereus was assessed during the storage of seasoned soybean sprouts at 0,5, 10, and $15^{\circ}C$. No lag time in its growth curve was observed and thus the specific growth rate of B. cereus in the exponential growth phase was estimated for bootstrapped microbial count data. The distribution of the specific growth rate could be explained by the BetaGeneral distribution function, and temperature dependence was described by the Ratkowsky square root model. The temperature dependence of the growth could be successfully incorporated into the differential equation of microbial growth to predict the B. cereus count on the seasoned soybean sprouts under fluctuating temperature conditions. Safe shelf lives with different probabilities to reach $10^5\;CFU/g$ were presented at four different temperatures, considering the variation in initial contamination and specific growth rate by the Monte Carlo method and 2-step bootstrapping, respectively. Safe shelf lives defined as the time with a probability of less than 0.1% of reaching the critical limit, were 13.4, 5.2, 3.6, and 2.8 days at 0, 5, 10, and $15^{\circ}C$, respectively.