• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.3
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• pp.11-18
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• 1991

Volatile organic compounds(VOC) present in or generated by many sources, can be toxic, mutagenic or even carcinogenic, so that control of such emissions is significant. The 6 chlorinated organic chemicals as VOC were examined in this study. Prediction of the behavior of VOC on activated carbon beds is an important part of control system design. The objective of this study was to predict gas phase sorption isotherms from physical properties and liquid phase isotherms obtained with the same adsorbent and adsorbate. One of the techniques that was investigated was quantitative structure-activity relationships(QSAR) for the predicition procedures. It was possible to estimate sorption isotherms in the gas phase($a_g$) using either connectivity index, $^2{\chi}$, and the Henry's law coefficient ($H_a$) or the solubility and the equilibrium concentration in the gas phase. As a result of study, the predictive equation based on Freundlich model for $a_g$ was ${\log}\;a_g=0.238\;^2{\chi}+0.573\;{\log}\;H_a+4.330(r^2=0.94)$. Finally, this would provide a potentially useful tool to describe and predict sorption capacity without time-consuming tests.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.403-406
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• 1997

Electrogastrogaphy(EGG) is the technique by which gastric myoelectrical activity is recorded noninvasively, from electrodes on the abdominal skin. Despite many attempts made over the decades, the clinical application of the EGG signal has not improved to the identification of waveform characteristics using comparison of EGG signal to be detected other EGG system. Cutaneous measurements of EGG are yet to be standardized in methods of detection and analysis. This may be responsible in part for some of the variability in the results. Thus, we develope EGG system composed of amplifiers, analysis methods, patient database or standardization. we introduce configurations of EGG system and their functions. Several important EGG parameters are introduced, including the dominant frequency and power of the EGG, the relative, period EGG-dominant frequency and power, the instability coefficient of EGG-dominant frequency and power, standard deviation, the percentage of running spectrum activity of gastric slow waves.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.172-178
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• 1998

Freezing-resistant plants can survive subzero temperatures by withstanding extracellular ice formation. During cold acclimation, their leaves accumulate antifreeze proteins (AFPs) that are secreted into the apoplast and have the ability to modify the normal growth of ice crystals. Three barley, two wheat and two rye cultivars were grown under two different temperature regimes (20/16$^{\circ}C$ and 5/2$^{\circ}C$, day/night). Apoplastic proteins from winter cereals were separated by SDS-PAGE and detected with antisera to AFPs from winter rye. Apoplastic proteins accumulated to much higher levels in cold-acclimated (CA) leaves compared with nonacclimated (NA) ones in winter cereals. After cold acclimation, the protein concentration of apoplastic extracts increased significantly from 0.088 $mgmL^{-1}$ to 0.448 $mgmL^{-1}$, with about 5-fold increment. Also, the apoplastic protein content per gram leaf fresh weight in CA leaves ranged from 31 $\mu\textrm{g}$ $(gFW)^{-1}$ to 120 $\mu\textrm{g}$ $(gFW)^{-1}$ with an averaged value of 77 $\mu\textrm{g}$ $(gFW)^{-1}$, and coefficients of variation of 54.9%. The CA leaves in Musketeer (a Canadian winter rye cultivar) showed the greatest AFPs and antifreeze activity followed by 'Geurumil' (a Korean winter wheat cultivar), and 'Dongbori l' (Korean facultative barley cultivar). The proteins secreted into the wheat leaf apoplast at CA condition were more numerous than those observed in winter rye, where two $\beta$-1,3-glucanase-like proteins (GLPs), two chitinase-like proteins (CLPs) and two thaumatin-like proteins (TLPs) accumulated during cold acclimation. The proteins in barley leaf apoplast at CA conditions were a little different from those in wheat leaves. The AFPs were various among and within species. More freezing-resistant cultivars had more clear and numerous bands than less freezing-resistant ones. The high determination coefficient ($R^2$ =91 %) between freezing resistance and AFPs per gram leaf fresh weight indicated that the amount of AFPs was highly related to freezing resistance in winter cereal crops.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.03a
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• pp.237-242
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• 1999

The nature of the interactions between the vestibular and autonomic systems is complex and has not been fully defined. Vestibuloocular reflex induced by sinusoidal rotation and activity of the autonomic nerves in the heart were measured to investigate the interactions between the vestibular system and the autonomic nervous system in healthy adults. Eye movement induced by sinusoidal rotation of the whole body or optokinetic stimulation at 0.04 Hz was analyzed in gain, phase, and symmetry. EKG was measured during vestibular stimulation and analyzed in heart rate variability including mean R-R interval, standard deviation (SD) and coefficient of variance (CV) of R-R interval, and power spectrum of low frequency region (LF) and high frequency region (HF). Gain of eye movement was 0.65${\pm}$0.03 by ratatory stimulation, 0.70${\pm}$0.02 in optokinetic stimulation, 0.08${\pm}$0.02 in visual suppression, and 0.84${\pm}$0.04 in visual enhancement. In R-R interval, resting condition (control) was 0.82${\pm}$0.03 sec, and visual suppression showed significant increase and visual enhancement did significant decrease compared with control (p<0.01).CV was 0.06${\pm}$0.02 in control and visual enhancement increased significantly (p<0.05). In LF/HF control was 1.40${\pm}$0.23, which was not different from rotatory or optokinetic stimulation. But visual suppression decreased LF/HF significantly and visual enhancement increased significantly compared with control (p<0.01). These results suggest that degree of gain corresponds with LF/HF and increased gain in visual enhancement is deeply related to the activity of sympathetic nerves.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.53-59
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• 1997

In this study investigated the effect of cytosine deaminase activity from Aspergillus fumigatus IFO 5840 by cytosine analogues. The results were as follows. The enzyme was strongly inibited by 2-thiouracil, 2-thiocytosine, 6-azacytosine and 2-mercaptopyrimidine. The half inhibitory concentration(HIC) of 2-thiocytosine and 6-azacytosine on cytosine deaminase was 0.80mM and 1.15mM, respectively. The enzyme was inhibited at a certain level by addition of 2-thiocytosine immediately, but was maintained to some extend under the inhibited state by 6-azacytosine in proportion to reaction time. Regardless of kinds of substrate such as cytosine and 5-fluorocytosine, 2-thiocytosine and 6-azacytosine showed action as inhibitors, 2-thiocytosine inhibited cytosine deaminase activity about twice as strong as 6-azacytosine. The enzyme, when cytosine was used as a substrate, was revealed the pattern of competitive inhibition by 2-thiocytosine and 6-azacytosine, The ki value for these compounds was 4.5$\times$10-4M and 1.756$\times$10-3M, respectively. At this point, the Hill coefficient for cytosine, 2-thiocytosine and 6-azacytosine was 1.80, 1.81 and 2.45, respectively.

• Journal of the Korean Ceramic Society
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• v.55 no.5
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• pp.446-451
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• 2018

In this study, different formulations of magnesium oxide and various modifiers (phosphoric acid, ferrous sulfate, pure acrylic emulsion, silicone acrylic emulsion, glass fiber, and polypropylene fiber) were used to prepare magnesium oxychloride cement composites. The compressive strength of the magnesium oxychloride cement was tested, and the softening coefficients of the composites after soaking in water were also calculated. The results showed that a magnesium oxychloride cement sample could not be coagulated when the MgO activity was 24.3%, but the coagulation effect of the magnesium oxide cement sample was excellent when the MgO activity was 69.5%. While pure acrylic emulsion, silicon-acrylic emulsion, and glass fiber showed insignificant modification effects on the magnesium oxychloride cement, ferrous sulfate heptahydrate, phosphoric acid, and polypropylene fiber could effectively improve its water resistance and compressive strength. When the phosphoric acid, ferrous sulfate heptahydrate, and polypropylene fiber contents were 0.47%, 0.73%, and 0.25%, respectively, the softening coefficient of a composite soaked in water reached 0.93 after 7 days, and the compressive strength reached 64.3 MPa.

• The Journal of Korean Academic Society of Nursing Education
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• v.26 no.4
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• pp.337-347
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• 2020

Purpose: The purpose of this study was to figure out the association of nursing activity participation and clinical practice stress with career maturity during clinical practice among nursing college students. Methods: Participants of the study were 201 nursing college students located in nationwide regions. Data collection was performed between July 18 and August 8, 2019. Data analyses were performed through an independent t-test, ANOVA, Pearson's correlation coefficient, and multiple linear regression analysis using SPSS WIN 25.0. Results: The results of this study were as follows. We ran multiple regression analyses to see which critical factors influenced career maturity. The general characteristics significantly associated with career maturity were preference for clinical nursing, admission to nursing college due to belief, time off, and being satisfied with clinical practice. Regarding clinical practice stress, clinic environment, interpersonal relationship conflict, inappropriate role model and conflict with patients were significantly associated with career maturity. Conclusion: This study suggested that, to improve nursing students' career maturity, nursing colleges and training fields should collaboratively make an efforts to reduce students' stress by building educational clinic environments including managing conflicts in interpersonal relationships among patients, caregivers, and medical and non-medical personnel, and improving inappropriate role models in nursing.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.661-666
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• 1998

Active reaction sites and electrochemical O2 reduction kinetics on La_{1-x}Sr_xMnO_{3+{\delta}} (x=0.1-0.4)/YSZ (yttria-stabilized zirconia) electrodes are investigated in the temperature range of 700-900 ℃ at $Po_2=10^{-3}$-0.21 atm. Results of the steady-state polarization measurements, which are formulated into the Butler-Volmer formalism to extract transfer coefficient values, lead us to conclude that the two-electron charge transfer step to atomically adsorbed oxygen is rate-limiting. The same conclusion is drawn from the $Po_2$-dependent ac impedance measurements, where the exponent m in the relationship of $I_o$ (exchange current density) ∝ $P_{o_{2}}^m$ is analyzed. Chemical analysis is performed on the quenched Mn perovskites to estimate their oxygen stoichiometry factors (δ) at the operating temperature (700-900 ℃). Here, the observed δ turns out to become smaller as both the Sr-doping contents (x) and the measured temperature increase. A comparison between the 8 values and cathodic activity of Mn perovskites reveals that the cathodic transfer coefficients $({\alpha}_c)$ for oxygen reduction reaction are inversely proportional to δ whereas the anodic ones $({\alpha}_a)$ show the opposite trend, reflecting that the surface oxygen vacancies on Mn perovskites actively participate in the $O_2$ reduction reaction. Among the samples of x= 0.1-0.4, the manganite with x=0.4 exhibits the smallest 8 value (even negative), and consistently this electrode shows the highest ${\alpha}_c$ and the best cathodic activity for the oxygen reduction reaction.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.71-80
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• 2019

This study is a descriptive research study to identify osteoporosis knowledge and osteoporosis prevention activities among care providers in nursing home. The subjects were 142 care providers in S and Y city. The Data were collected from July 1 to July 20, 2019, and analyzed SPSS 24.0 Version. The result showed that the osteoporosis knowledge of among care providers was moderate. It showed differences in educational status, osteoporosis management training experience, residents number and importance awareness of elderly bone health. And prevention activities differed according to osteoporosis management training experience and importance awareness of elderly bone health. There was a positive correlation between knowledge and prevention activities of osteoporosis. Therefore, it is necessary to develop education programs for the management of elderly osteoporosis and to raise importance awareness of elderly bone health among care providers in nursing home. Further studies are needed to evaluate the effects of the program.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.347-354
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• 2019

Purpose: The purpose of this study was to determine the relationships among health related quality of life and uncertainty in adult patients with congenital heart diseases. Methods: The subjects were 136 adult congenital heart disease patients at the congenital heart center out-patient clinic of the A General Hospital in S city. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient and multiple regression. Results: There were significant negative correlations of quality of life with general motor function area and uncertainty. Among predictors, gross motor(${\beta}=-.38$) and daily activity (${\beta}=-.21$) had statistically significant influences on uncertainty(F=6.15, p=.018). Conclusion: Nursing interventions to promote gross motor and daily activity might be essential for adult patients with congenital heart disease in order to reduce uncertainty.